diff --git a/addons/knobs/src/components/types/Array.tsx b/addons/knobs/src/components/types/Array.tsx
index 6f198878bd9d..a0a1fb81e02d 100644
--- a/addons/knobs/src/components/types/Array.tsx
+++ b/addons/knobs/src/components/types/Array.tsx
@@ -1,25 +1,61 @@
 import PropTypes from 'prop-types';
-import React from 'react';
+import React, { Component, WeakValidationMap } from 'react';
 
 import { Form } from '@storybook/components';
 
-function formatArray(value, separator) {
+type ArrayTypeKnobValue = string[];
+
+interface ArrayTypeProps {
+  knob: {
+    name: string;
+    value: ArrayTypeKnobValue;
+    separator: string;
+  };
+  onChange: (value: ArrayTypeKnobValue) => ArrayTypeKnobValue;
+}
+
+function formatArray(value: string, separator: string) {
   if (value === '') {
     return [];
   }
   return value.split(separator);
 }
 
-class ArrayType extends React.Component {
-  shouldComponentUpdate(nextProps) {
+export default class ArrayType extends Component<ArrayTypeProps> {
+  static defaultProps: Partial<ArrayTypeProps> = {
+    knob: {} as any,
+    onChange: (value: ArrayTypeKnobValue) => value,
+  };
+
+  static propTypes: WeakValidationMap<ArrayTypeProps> = {
+    // TODO: remove `any` once DefinitelyTyped/DefinitelyTyped#31280 has been resolved
+    knob: PropTypes.shape({
+      name: PropTypes.string,
+      value: PropTypes.array,
+      separator: PropTypes.string,
+    }) as any,
+    onChange: PropTypes.func,
+  };
+
+  static serialize = (value: ArrayTypeKnobValue) => value;
+
+  static deserialize = (value: ArrayTypeKnobValue) => {
+    if (Array.isArray(value)) return value;
+
+    return Object.keys(value)
+      .sort()
+      .reduce((array, key) => [...array, value[key]], []);
+  };
+
+  shouldComponentUpdate(nextProps: Readonly<ArrayTypeProps>) {
     const { knob } = this.props;
 
     return nextProps.knob.value !== knob.value;
   }
 
-  handleChange = e => {
+  handleChange = (e: Event) => {
     const { knob, onChange } = this.props;
-    const { value } = e.target;
+    const { value } = e.target as HTMLTextAreaElement;
     const newVal = formatArray(value, knob.separator);
 
     onChange(newVal);
@@ -40,28 +76,3 @@ class ArrayType extends React.Component {
     );
   }
 }
-
-ArrayType.defaultProps = {
-  knob: {},
-  onChange: value => value,
-};
-
-ArrayType.propTypes = {
-  knob: PropTypes.shape({
-    name: PropTypes.string,
-    value: PropTypes.array,
-    separator: PropTypes.string,
-  }),
-  onChange: PropTypes.func,
-};
-
-ArrayType.serialize = value => value;
-ArrayType.deserialize = value => {
-  if (Array.isArray(value)) return value;
-
-  return Object.keys(value)
-    .sort()
-    .reduce((array, key) => [...array, value[key]], []);
-};
-
-export default ArrayType;
diff --git a/addons/knobs/src/components/types/Boolean.tsx b/addons/knobs/src/components/types/Boolean.tsx
index 8264f47fee28..818aa5ef1084 100644
--- a/addons/knobs/src/components/types/Boolean.tsx
+++ b/addons/knobs/src/components/types/Boolean.tsx
@@ -1,8 +1,19 @@
 import PropTypes from 'prop-types';
-import React from 'react';
+import React, { FunctionComponent } from 'react';
 
 import { styled } from '@storybook/theming';
 
+type BooleanTypeKnobValue = boolean;
+
+interface BooleanTypeProps {
+  knob: {
+    name: string;
+    value: BooleanTypeKnobValue;
+    separator: string;
+  };
+  onChange: (value: BooleanTypeKnobValue) => BooleanTypeKnobValue;
+}
+
 const Input = styled.input({
   display: 'table-cell',
   boxSizing: 'border-box',
@@ -14,7 +25,13 @@ const Input = styled.input({
   color: '#555',
 });
 
-const BooleanType = ({ knob, onChange }) => (
+const serialize = (value: BooleanTypeKnobValue): string | null => (value ? String(value) : null);
+const deserialize = (value: string | null) => value === 'true';
+
+const BooleanType: FunctionComponent<BooleanTypeProps> & {
+  serialize: typeof serialize;
+  deserialize: typeof deserialize;
+} = ({ knob, onChange }) => (
   <Input
     id={knob.name}
     name={knob.name}
@@ -25,19 +42,20 @@ const BooleanType = ({ knob, onChange }) => (
 );
 
 BooleanType.defaultProps = {
-  knob: {},
+  knob: {} as any,
   onChange: value => value,
 };
 
 BooleanType.propTypes = {
+  // TODO: remove `any` once DefinitelyTyped/DefinitelyTyped#31280 has been resolved
   knob: PropTypes.shape({
     name: PropTypes.string,
     value: PropTypes.bool,
-  }),
+  }) as any,
   onChange: PropTypes.func,
 };
 
-BooleanType.serialize = value => (value ? String(value) : null);
-BooleanType.deserialize = value => value === 'true';
+BooleanType.serialize = serialize;
+BooleanType.deserialize = deserialize;
 
 export default BooleanType;
diff --git a/addons/knobs/src/components/types/Button.tsx b/addons/knobs/src/components/types/Button.tsx
index 39b0a07f5780..d5cd6d13d8cb 100644
--- a/addons/knobs/src/components/types/Button.tsx
+++ b/addons/knobs/src/components/types/Button.tsx
@@ -1,22 +1,42 @@
 import PropTypes from 'prop-types';
-import React from 'react';
+import React, { FunctionComponent, Validator } from 'react';
 
 import { Form } from '@storybook/components';
 
-const ButtonType = ({ knob, onClick }) => (
+interface ButtonTypeKnobProp {
+  name: string;
+}
+
+interface ButtonTypeProps {
+  knob: ButtonTypeKnobProp;
+  onClick: (knob: ButtonTypeKnobProp) => any;
+}
+
+const serialize = (): undefined => undefined;
+const deserialize = (): undefined => undefined;
+
+const ButtonType: FunctionComponent<ButtonTypeProps> & {
+  serialize: typeof serialize;
+  deserialize: typeof deserialize;
+} = ({ knob, onClick }) => (
   <Form.Button type="button" name={knob.name} onClick={() => onClick(knob)}>
     {knob.name}
   </Form.Button>
 );
 
+ButtonType.defaultProps = {
+  knob: {} as any,
+};
+
 ButtonType.propTypes = {
+  // TODO: remove `any` once DefinitelyTyped/DefinitelyTyped#31280 has been resolved
   knob: PropTypes.shape({
     name: PropTypes.string,
-  }).isRequired,
+  }).isRequired as Validator<any>,
   onClick: PropTypes.func.isRequired,
 };
 
-ButtonType.serialize = () => undefined;
-ButtonType.deserialize = () => undefined;
+ButtonType.serialize = serialize;
+ButtonType.deserialize = deserialize;
 
 export default ButtonType;
diff --git a/addons/knobs/src/components/types/Checkboxes.tsx b/addons/knobs/src/components/types/Checkboxes.tsx
index a15cf1d64126..1765c014d2df 100644
--- a/addons/knobs/src/components/types/Checkboxes.tsx
+++ b/addons/knobs/src/components/types/Checkboxes.tsx
@@ -1,8 +1,33 @@
-import React, { Component } from 'react';
+import React, { Component, ChangeEvent, WeakValidationMap } from 'react';
 import PropTypes from 'prop-types';
 import { styled } from '@storybook/theming';
 
-const CheckboxesWrapper = styled.div(({ isInline }) =>
+type CheckboxesTypeKnobValue = string[];
+
+interface CheckboxesWrapperProps {
+  isInline: boolean;
+}
+
+interface CheckboxesTypeKnobProp {
+  name: string;
+  value: CheckboxesTypeKnobValue;
+  defaultValue: CheckboxesTypeKnobValue;
+  options: {
+    [key: string]: string;
+  };
+}
+
+interface CheckboxesTypeProps {
+  knob: CheckboxesTypeKnobProp;
+  isInline: boolean;
+  onChange: (value: CheckboxesTypeKnobValue) => CheckboxesTypeKnobValue;
+}
+
+interface CheckboxesTypeState {
+  values: CheckboxesTypeKnobValue;
+}
+
+const CheckboxesWrapper = styled.div(({ isInline }: CheckboxesWrapperProps) =>
   isInline
     ? {
         display: 'flex',
@@ -27,8 +52,29 @@ const CheckboxLabel = styled.label({
   display: 'inline-block',
 });
 
-class CheckboxesType extends Component {
-  constructor(props) {
+export default class CheckboxesType extends Component<CheckboxesTypeProps, CheckboxesTypeState> {
+  static defaultProps: CheckboxesTypeProps = {
+    knob: {} as any,
+    onChange: value => value,
+    isInline: false,
+  };
+
+  static propTypes: WeakValidationMap<CheckboxesTypeProps> = {
+    // TODO: remove `any` once DefinitelyTyped/DefinitelyTyped#31280 has been resolved
+    knob: PropTypes.shape({
+      name: PropTypes.string,
+      value: PropTypes.array,
+      options: PropTypes.oneOfType([PropTypes.array, PropTypes.object]),
+    }) as any,
+    onChange: PropTypes.func,
+    isInline: PropTypes.bool,
+  };
+
+  static serialize = (value: CheckboxesTypeKnobValue) => value;
+
+  static deserialize = (value: CheckboxesTypeKnobValue) => value;
+
+  constructor(props: CheckboxesTypeProps) {
     super(props);
     const { knob } = props;
 
@@ -37,9 +83,9 @@ class CheckboxesType extends Component {
     };
   }
 
-  handleChange = e => {
+  handleChange = (e: ChangeEvent<HTMLInputElement>) => {
     const { onChange } = this.props;
-    const currentValue = e.target.value;
+    const currentValue = (e.target as HTMLInputElement).value;
     const { values } = this.state;
 
     if (values.includes(currentValue)) {
@@ -53,10 +99,10 @@ class CheckboxesType extends Component {
     onChange(values);
   };
 
-  renderCheckboxList = ({ options }) =>
+  renderCheckboxList = ({ options }: CheckboxesTypeKnobProp) =>
     Object.keys(options).map(key => this.renderCheckbox(key, options[key]));
 
-  renderCheckbox = (label, value) => {
+  renderCheckbox = (label: string, value: string) => {
     const { knob } = this.props;
     const { name } = knob;
     const id = `${name}-${value}`;
@@ -87,24 +133,3 @@ class CheckboxesType extends Component {
     );
   }
 }
-
-CheckboxesType.defaultProps = {
-  knob: {},
-  onChange: value => value,
-  isInline: false,
-};
-
-CheckboxesType.propTypes = {
-  knob: PropTypes.shape({
-    name: PropTypes.string,
-    value: PropTypes.array,
-    options: PropTypes.oneOfType([PropTypes.array, PropTypes.object]),
-  }),
-  onChange: PropTypes.func,
-  isInline: PropTypes.bool,
-};
-
-CheckboxesType.serialize = value => value;
-CheckboxesType.deserialize = value => value;
-
-export default CheckboxesType;
diff --git a/addons/knobs/src/components/types/Color.tsx b/addons/knobs/src/components/types/Color.tsx
index 1b440d615616..43c3c2a20f5e 100644
--- a/addons/knobs/src/components/types/Color.tsx
+++ b/addons/knobs/src/components/types/Color.tsx
@@ -1,12 +1,45 @@
+// @ts-ignore
 import { document } from 'global';
 import PropTypes from 'prop-types';
-import React from 'react';
+import React, { Component, WeakValidationMap } from 'react';
+// @ts-ignore
 import { SketchPicker } from 'react-color';
 
 import { styled } from '@storybook/theming';
-
 import { Form } from '@storybook/components';
 
+type ColorTypeKnobValue = string;
+
+interface ColorTypeProps {
+  knob: {
+    name: string;
+    value: ColorTypeKnobValue;
+  };
+  onChange: (value: ColorTypeKnobValue) => ColorTypeKnobValue;
+}
+
+interface ColorTypeState {
+  displayColorPicker: boolean;
+}
+
+interface ColorButtonProps {
+  name: string;
+  type: string;
+  size: string;
+  active: boolean;
+  onClick: () => any;
+}
+
+// TODO: These types should come from @types/react-color once installed
+interface ColorResult {
+  rgb: {
+    a?: number;
+    b: number;
+    g: number;
+    r: number;
+  };
+}
+
 const { Button } = Form;
 
 const Swatch = styled.div(({ theme }) => ({
@@ -20,25 +53,45 @@ const Swatch = styled.div(({ theme }) => ({
   borderRadius: '1rem',
 }));
 
-const ColorButton = styled(Button)(({ active }) => ({
+const ColorButton = styled(Button)(({ active }: ColorButtonProps) => ({
   zIndex: active ? 3 : 'unset',
 }));
 
 const Popover = styled.div({
   position: 'absolute',
-  zIndex: '2',
+  zIndex: 2,
 });
 
-class ColorType extends React.Component {
-  state = {
+export default class ColorType extends Component<ColorTypeProps, ColorTypeState> {
+  static propTypes: WeakValidationMap<ColorTypeProps> = {
+    // TODO: remove `any` once DefinitelyTyped/DefinitelyTyped#31280 has been resolved
+    knob: PropTypes.shape({
+      name: PropTypes.string,
+      value: PropTypes.string,
+    }) as any,
+    onChange: PropTypes.func,
+  };
+
+  static defaultProps: ColorTypeProps = {
+    knob: {} as any,
+    onChange: value => value,
+  };
+
+  static serialize = (value: ColorTypeKnobValue) => value;
+
+  static deserialize = (value: ColorTypeKnobValue) => value;
+
+  state: ColorTypeState = {
     displayColorPicker: false,
   };
 
+  popover: HTMLDivElement;
+
   componentDidMount() {
     document.addEventListener('mousedown', this.handleWindowMouseDown);
   }
 
-  shouldComponentUpdate(nextProps, nextState) {
+  shouldComponentUpdate(nextProps: ColorTypeProps, nextState: ColorTypeState) {
     const { knob } = this.props;
     const { displayColorPicker } = this.state;
 
@@ -51,9 +104,9 @@ class ColorType extends React.Component {
     document.removeEventListener('mousedown', this.handleWindowMouseDown);
   }
 
-  handleWindowMouseDown = e => {
+  handleWindowMouseDown = (e: MouseEvent) => {
     const { displayColorPicker } = this.state;
-    if (!displayColorPicker || this.popover.contains(e.target)) {
+    if (!displayColorPicker || this.popover.contains(e.target as HTMLElement)) {
       return;
     }
 
@@ -70,7 +123,7 @@ class ColorType extends React.Component {
     });
   };
 
-  handleChange = color => {
+  handleChange = (color: ColorResult) => {
     const { onChange } = this.props;
 
     onChange(`rgba(${color.rgb.r},${color.rgb.g},${color.rgb.b},${color.rgb.a})`);
@@ -105,20 +158,3 @@ class ColorType extends React.Component {
     );
   }
 }
-
-ColorType.propTypes = {
-  knob: PropTypes.shape({
-    name: PropTypes.string,
-    value: PropTypes.string,
-  }),
-  onChange: PropTypes.func,
-};
-ColorType.defaultProps = {
-  knob: {},
-  onChange: value => value,
-};
-
-ColorType.serialize = value => value;
-ColorType.deserialize = value => value;
-
-export default ColorType;
diff --git a/addons/knobs/src/components/types/Date.tsx b/addons/knobs/src/components/types/Date.tsx
index f645fcca9e68..e1fb6cccb665 100644
--- a/addons/knobs/src/components/types/Date.tsx
+++ b/addons/knobs/src/components/types/Date.tsx
@@ -1,8 +1,22 @@
-import React, { Component } from 'react';
+import React, { Component, ChangeEvent, WeakValidationMap } from 'react';
 import PropTypes from 'prop-types';
 import { styled } from '@storybook/theming';
 import { Form } from '@storybook/components';
 
+type DateTypeKnobValue = number;
+
+interface DateTypeProps {
+  knob: {
+    name: string;
+    value: DateTypeKnobValue;
+  };
+  onChange: (value: DateTypeKnobValue) => DateTypeKnobValue;
+}
+
+interface DateTypeState {
+  valid: boolean | undefined;
+}
+
 const FlexSpaced = styled.div({
   flex: 1,
   display: 'flex',
@@ -15,29 +29,54 @@ const FlexSpaced = styled.div({
 });
 const FlexInput = styled(Form.Input)({ flex: 1 });
 
-const formatDate = date => {
+const formatDate = (date: Date) => {
   const year = `000${date.getFullYear()}`.slice(-4);
   const month = `0${date.getMonth() + 1}`.slice(-2);
   const day = `0${date.getDate()}`.slice(-2);
 
   return `${year}-${month}-${day}`;
 };
-const formatTime = date => {
+
+const formatTime = (date: Date) => {
   const hours = `0${date.getHours()}`.slice(-2);
   const minutes = `0${date.getMinutes()}`.slice(-2);
 
   return `${hours}:${minutes}`;
 };
 
-class DateType extends Component {
+export default class DateType extends Component<DateTypeProps, DateTypeState> {
+  static defaultProps: DateTypeProps = {
+    knob: {} as any,
+    onChange: value => value,
+  };
+
+  static propTypes: WeakValidationMap<DateTypeProps> = {
+    // TODO: remove `any` once DefinitelyTyped/DefinitelyTyped#31280 has been resolved
+    knob: PropTypes.shape({
+      name: PropTypes.string,
+      value: PropTypes.number,
+    }) as any,
+    onChange: PropTypes.func,
+  };
+
+  static serialize = (value: DateTypeKnobValue) =>
+    new Date(value).getTime() || new Date().getTime();
+
+  static deserialize = (value: DateTypeKnobValue) =>
+    new Date(value).getTime() || new Date().getTime();
+
   static getDerivedStateFromProps() {
     return { valid: true };
   }
 
-  state = {
+  state: DateTypeState = {
     valid: undefined,
   };
 
+  dateInput: HTMLInputElement;
+
+  timeInput: HTMLInputElement;
+
   componentDidUpdate() {
     const { knob } = this.props;
     const { valid } = this.state;
@@ -49,7 +88,7 @@ class DateType extends Component {
     }
   }
 
-  onDateChange = e => {
+  onDateChange = (e: ChangeEvent<HTMLInputElement>) => {
     const { knob, onChange } = this.props;
     const { state } = this;
 
@@ -70,7 +109,7 @@ class DateType extends Component {
     }
   };
 
-  onTimeChange = e => {
+  onTimeChange = (e: ChangeEvent<HTMLInputElement>) => {
     const { knob, onChange } = this.props;
     const { state } = this;
 
@@ -100,7 +139,7 @@ class DateType extends Component {
         <FlexInput
           type="date"
           max="9999-12-31" // I do this because of a rendering bug in chrome
-          ref={el => {
+          ref={(el: HTMLInputElement) => {
             this.dateInput = el;
           }}
           id={`${name}date`}
@@ -111,7 +150,7 @@ class DateType extends Component {
           type="time"
           id={`${name}time`}
           name={`${name}time`}
-          ref={el => {
+          ref={(el: HTMLInputElement) => {
             this.timeInput = el;
           }}
           onChange={this.onTimeChange}
@@ -121,21 +160,3 @@ class DateType extends Component {
     ) : null;
   }
 }
-
-DateType.defaultProps = {
-  knob: {},
-  onChange: value => value,
-};
-
-DateType.propTypes = {
-  knob: PropTypes.shape({
-    name: PropTypes.string,
-    value: PropTypes.number,
-  }),
-  onChange: PropTypes.func,
-};
-
-DateType.serialize = value => new Date(value).getTime() || new Date().getTime();
-DateType.deserialize = value => new Date(value).getTime() || new Date().getTime();
-
-export default DateType;
diff --git a/addons/knobs/src/components/types/Files.tsx b/addons/knobs/src/components/types/Files.tsx
index 797498d2b935..628e7fb0f00a 100644
--- a/addons/knobs/src/components/types/Files.tsx
+++ b/addons/knobs/src/components/types/Files.tsx
@@ -1,46 +1,67 @@
+// @ts-ignore
 import { FileReader } from 'global';
 import PropTypes from 'prop-types';
-import React from 'react';
+import React, { ChangeEvent, FunctionComponent } from 'react';
 import { styled } from '@storybook/theming';
 
 import { Form } from '@storybook/components';
 
+type DateTypeKnobValue = string[];
+
+interface FilesTypeProps {
+  knob: {
+    name: string;
+    accept: string;
+    value: DateTypeKnobValue;
+  };
+  onChange: (value: DateTypeKnobValue) => DateTypeKnobValue;
+}
+
 const FileInput = styled(Form.Input)({
   paddingTop: 4,
 });
 
-function fileReaderPromise(file) {
-  return new Promise(resolve => {
+function fileReaderPromise(file: File) {
+  return new Promise<string>(resolve => {
     const fileReader = new FileReader();
-    fileReader.onload = e => resolve(e.currentTarget.result);
+    fileReader.onload = (e: Event) => resolve((e.currentTarget as FileReader).result);
     fileReader.readAsDataURL(file);
   });
 }
 
-const FilesType = ({ knob, onChange }) => (
+const serialize = (): undefined => undefined;
+const deserialize = (): undefined => undefined;
+
+const FilesType: FunctionComponent<FilesTypeProps> & {
+  serialize: typeof serialize;
+  deserialize: typeof deserialize;
+} = ({ knob, onChange }) => (
   <FileInput
     type="file"
     name={knob.name}
     multiple
-    onChange={e => Promise.all(Array.from(e.target.files).map(fileReaderPromise)).then(onChange)}
+    onChange={(e: ChangeEvent<HTMLInputElement>) =>
+      Promise.all(Array.from(e.target.files).map(fileReaderPromise)).then(onChange)
+    }
     accept={knob.accept}
     size="flex"
   />
 );
 
 FilesType.defaultProps = {
-  knob: {},
+  knob: {} as any,
   onChange: value => value,
 };
 
 FilesType.propTypes = {
+  // TODO: remove `any` once DefinitelyTyped/DefinitelyTyped#31280 has been resolved
   knob: PropTypes.shape({
     name: PropTypes.string,
-  }),
+  }) as any,
   onChange: PropTypes.func,
 };
 
-FilesType.serialize = () => undefined;
-FilesType.deserialize = () => undefined;
+FilesType.serialize = serialize;
+FilesType.deserialize = deserialize;
 
 export default FilesType;
diff --git a/addons/knobs/src/components/types/Number.tsx b/addons/knobs/src/components/types/Number.tsx
index 9a6b677cb8f5..e27b3189ea3d 100644
--- a/addons/knobs/src/components/types/Number.tsx
+++ b/addons/knobs/src/components/types/Number.tsx
@@ -1,45 +1,78 @@
 import PropTypes from 'prop-types';
-import React from 'react';
+import React, { Component, ChangeEvent } from 'react';
 
 import { styled } from '@storybook/theming';
-
 import { Form } from '@storybook/components';
 
-const base = {
-  boxSizing: 'border-box',
-  height: '25px',
-  outline: 'none',
-  border: '1px solid #f7f4f4',
-  borderRadius: 2,
-  fontSize: 11,
-  padding: '5px',
-  color: '#444',
-};
-
-const RangeInput = styled.input(base, {
-  display: 'table-cell',
-  flexGrow: 1,
-});
+type NumberTypeKnobValue = number;
+
+interface NumberTypeProps {
+  knob: {
+    name: string;
+    value: number;
+    range?: boolean;
+    min?: number;
+    max?: number;
+    step?: number;
+  };
+  onChange: (value: NumberTypeKnobValue) => NumberTypeKnobValue;
+}
+
+const RangeInput = styled.input(
+  {
+    boxSizing: 'border-box',
+    height: '25px',
+    outline: 'none',
+    border: '1px solid #f7f4f4',
+    borderRadius: 2,
+    fontSize: 11,
+    padding: '5px',
+    color: '#444',
+  },
+  {
+    display: 'table-cell',
+    flexGrow: 1,
+  }
+);
+
 const RangeLabel = styled.span({
   paddingLeft: 5,
   paddingRight: 5,
   fontSize: 12,
   whiteSpace: 'nowrap',
 });
+
 const RangeWrapper = styled.div({
   display: 'flex',
   alignItems: 'center',
   width: '100%',
 });
 
-class NumberType extends React.Component {
-  shouldComponentUpdate(nextProps) {
+export default class NumberType extends Component<NumberTypeProps> {
+  static propTypes = {
+    knob: PropTypes.shape({
+      name: PropTypes.string,
+      value: PropTypes.oneOfType([PropTypes.string, PropTypes.number]),
+      range: PropTypes.bool,
+      min: PropTypes.number,
+      max: PropTypes.number,
+      step: PropTypes.number,
+    }).isRequired,
+    onChange: PropTypes.func.isRequired,
+  };
+
+  static serialize = (value: NumberTypeKnobValue | null | undefined) =>
+    value === null || value === undefined ? '' : String(value);
+
+  static deserialize = (value: string) => (value === '' ? null : parseFloat(value));
+
+  shouldComponentUpdate(nextProps: NumberTypeProps) {
     const { knob } = this.props;
 
     return nextProps.knob.value !== knob.value;
   }
 
-  handleChange = event => {
+  handleChange = (event: ChangeEvent<HTMLInputElement>) => {
     const { onChange } = this.props;
     const { value } = event.target;
 
@@ -83,20 +116,3 @@ class NumberType extends React.Component {
     );
   }
 }
-
-NumberType.propTypes = {
-  knob: PropTypes.shape({
-    name: PropTypes.string,
-    value: PropTypes.oneOfType([PropTypes.string, PropTypes.number]),
-    range: PropTypes.bool,
-    min: PropTypes.number,
-    max: PropTypes.number,
-    step: PropTypes.number,
-  }).isRequired,
-  onChange: PropTypes.func.isRequired,
-};
-
-NumberType.serialize = value => (value === null || value === undefined ? '' : String(value));
-NumberType.deserialize = value => (value === '' ? null : parseFloat(value));
-
-export default NumberType;
diff --git a/addons/knobs/src/components/types/Object.tsx b/addons/knobs/src/components/types/Object.tsx
index b68e55e24fa5..c3a3c245c86b 100644
--- a/addons/knobs/src/components/types/Object.tsx
+++ b/addons/knobs/src/components/types/Object.tsx
@@ -1,17 +1,41 @@
-import React, { Component } from 'react';
+import React, { Component, ChangeEvent } from 'react';
 import PropTypes from 'prop-types';
 import deepEqual from 'fast-deep-equal';
+// @ts-ignore
 import { polyfill } from 'react-lifecycles-compat';
 import { Form } from '@storybook/components';
 
-class ObjectType extends Component {
-  state = {
-    value: {},
-    failed: false,
-    json: '',
+interface ObjectTypeProps<T> {
+  knob: {
+    name: string;
+    value: T;
   };
+  onChange: (value: T) => T;
+}
+
+interface ObjectTypeState<T> {
+  value: string;
+  failed: boolean;
+  json?: T;
+}
+
+class ObjectType<T> extends Component<ObjectTypeProps<T>> {
+  static propTypes = {
+    knob: PropTypes.shape({
+      name: PropTypes.string,
+      value: PropTypes.oneOfType([PropTypes.object, PropTypes.array]),
+    }).isRequired,
+    onChange: PropTypes.func.isRequired,
+  };
+
+  static serialize: { <T>(object: T): string } = object => JSON.stringify(object);
 
-  static getDerivedStateFromProps(props, state) {
+  static deserialize: { <T>(value: string): T } = value => (value ? JSON.parse(value) : {});
+
+  static getDerivedStateFromProps<T>(
+    props: ObjectTypeProps<T>,
+    state: ObjectTypeState<T>
+  ): ObjectTypeState<T> {
     if (!deepEqual(props.knob.value, state.json)) {
       try {
         return {
@@ -26,7 +50,13 @@ class ObjectType extends Component {
     return null;
   }
 
-  handleChange = e => {
+  state: ObjectTypeState<T> = {
+    value: '',
+    failed: false,
+    json: {} as any,
+  };
+
+  handleChange = (e: ChangeEvent<HTMLTextAreaElement>) => {
     const { value } = e.target;
     const { json: stateJson } = this.state;
     const { knob, onChange } = this.props;
@@ -65,17 +95,6 @@ class ObjectType extends Component {
   }
 }
 
-ObjectType.propTypes = {
-  knob: PropTypes.shape({
-    name: PropTypes.string,
-    value: PropTypes.oneOfType([PropTypes.object, PropTypes.array]),
-  }).isRequired,
-  onChange: PropTypes.func.isRequired,
-};
-
-ObjectType.serialize = object => JSON.stringify(object);
-ObjectType.deserialize = value => (value ? JSON.parse(value) : {});
-
 polyfill(ObjectType);
 
 export default ObjectType;
diff --git a/addons/knobs/src/components/types/Options.tsx b/addons/knobs/src/components/types/Options.tsx
index 8580f72d7d44..0ce43e5b17cd 100644
--- a/addons/knobs/src/components/types/Options.tsx
+++ b/addons/knobs/src/components/types/Options.tsx
@@ -1,5 +1,6 @@
-import React from 'react';
+import React, { FunctionComponent } from 'react';
 import PropTypes from 'prop-types';
+// @ts-ignore
 import ReactSelect from 'react-select';
 import { styled } from '@storybook/theming';
 
@@ -8,13 +9,67 @@ import CheckboxesType from './Checkboxes';
 
 // TODO: Apply the Storybook theme to react-select
 
-const OptionsSelect = styled(ReactSelect)({
+export type OptionsKnobOptionsDisplay =
+  | 'radio'
+  | 'inline-radio'
+  | 'check'
+  | 'inline-check'
+  | 'select'
+  | 'multi-select';
+
+export interface OptionsKnobOptions {
+  display?: OptionsKnobOptionsDisplay;
+}
+
+interface OptionsTypeProps<T> {
+  knob: {
+    name: string;
+    value: T;
+    defaultValue: T;
+    options: {
+      [key: string]: T;
+    };
+    optionsObj: OptionsKnobOptions;
+  };
+  display: OptionsKnobOptionsDisplay;
+  onChange: (value: T) => T;
+}
+
+const OptionsSelect: React.ComponentType<ReactSelectProps> = styled(ReactSelect)({
   width: '100%',
   maxWidth: '300px',
   color: 'black',
 });
 
-const OptionsType = props => {
+// TODO: These types should come from @types/react-select once installed.
+type ReactSelectValueType<OptionType = { label: string; value: string }> =
+  | OptionType
+  | OptionsType<OptionType>
+  | null
+  | undefined;
+
+type ReactSelectOnChangeFn<OptionType = { label: string; value: string }> = (
+  value: ReactSelectValueType<OptionType>
+) => void;
+
+interface ReactSelectProps {
+  value: OptionsSelectValueItem | OptionsSelectValueItem[];
+  options: any;
+  isMulti: boolean;
+  onChange: ReactSelectOnChangeFn;
+}
+interface OptionsSelectValueItem {
+  value: any;
+  label: string;
+}
+
+const serialize: { <T>(value: T): T } = value => value;
+const deserialize: { <T>(value: T): T } = value => value;
+
+const OptionsType: FunctionComponent<OptionsTypeProps<any>> & {
+  serialize: typeof serialize;
+  deserialize: typeof deserialize;
+} = props => {
   const { knob, onChange } = props;
   const { display } = knob.optionsObj;
 
@@ -29,19 +84,19 @@ const OptionsType = props => {
   }
 
   if (display === 'select' || display === 'multi-select') {
-    const options = Object.keys(knob.options).map(key => ({
+    const options: OptionsSelectValueItem[] = Object.keys(knob.options).map(key => ({
       value: knob.options[key],
       label: key,
     }));
 
     const isMulti = display === 'multi-select';
     const optionsIndex = options.findIndex(i => i.value === knob.value);
-    let defaultValue = options[optionsIndex];
-    let handleChange = e => onChange(e.value);
+    let defaultValue: typeof options | typeof options[0] = options[optionsIndex];
+    let handleChange: ReactSelectOnChangeFn = (e: OptionsSelectValueItem) => onChange(e.value);
 
     if (isMulti) {
       defaultValue = options.filter(i => knob.value.includes(i.value));
-      handleChange = values => onChange(values.map(item => item.value));
+      handleChange = (values: OptionsSelectValueItem[]) => onChange(values.map(item => item.value));
     }
 
     return (
@@ -53,33 +108,35 @@ const OptionsType = props => {
       />
     );
   }
+
   return null;
 };
 
 OptionsType.defaultProps = {
-  knob: {},
+  knob: {} as any,
   display: 'select',
   onChange: value => value,
 };
 
 OptionsType.propTypes = {
+  // TODO: remove `any` once DefinitelyTyped/DefinitelyTyped#31280 has been resolved
   knob: PropTypes.shape({
     name: PropTypes.string,
     value: PropTypes.oneOfType([PropTypes.array, PropTypes.string]),
     options: PropTypes.object,
-  }),
-  display: PropTypes.oneOf([
-    'check',
-    'inline-check',
+  }) as any,
+  display: PropTypes.oneOf<OptionsKnobOptionsDisplay>([
     'radio',
     'inline-radio',
+    'check',
+    'inline-check',
     'select',
     'multi-select',
   ]),
   onChange: PropTypes.func,
 };
 
-OptionsType.serialize = value => value;
-OptionsType.deserialize = value => value;
+OptionsType.serialize = serialize;
+OptionsType.deserialize = deserialize;
 
 export default OptionsType;
diff --git a/addons/knobs/src/components/types/Radio.tsx b/addons/knobs/src/components/types/Radio.tsx
index f4163967e2ea..b9d9bc094c0e 100644
--- a/addons/knobs/src/components/types/Radio.tsx
+++ b/addons/knobs/src/components/types/Radio.tsx
@@ -1,8 +1,29 @@
-import React, { Component } from 'react';
+import React, { Component, WeakValidationMap } from 'react';
 import PropTypes from 'prop-types';
 import { styled } from '@storybook/theming';
 
-const RadiosWrapper = styled.div(({ isInline }) =>
+type RadiosTypeKnobValue = string;
+
+interface RadiosTypeKnobProp {
+  name: string;
+  value: RadiosTypeKnobValue;
+  defaultValue: RadiosTypeKnobValue;
+  options: {
+    [key: string]: RadiosTypeKnobValue;
+  };
+}
+
+interface RadiosTypeProps {
+  knob: RadiosTypeKnobProp;
+  isInline: boolean;
+  onChange: (value: RadiosTypeKnobValue) => RadiosTypeKnobValue;
+}
+
+interface RadiosWrapperProps {
+  isInline: boolean;
+}
+
+const RadiosWrapper = styled.div(({ isInline }: RadiosWrapperProps) =>
   isInline
     ? {
         display: 'flex',
@@ -21,15 +42,36 @@ const RadioLabel = styled.label({
   display: 'inline-block',
 });
 
-class RadiosType extends Component {
-  renderRadioButtonList({ options }) {
+class RadiosType extends Component<RadiosTypeProps> {
+  static defaultProps: RadiosTypeProps = {
+    knob: {} as any,
+    onChange: value => value,
+    isInline: false,
+  };
+
+  static propTypes: WeakValidationMap<RadiosTypeProps> = {
+    // TODO: remove `any` once DefinitelyTyped/DefinitelyTyped#31280 has been resolved
+    knob: PropTypes.shape({
+      name: PropTypes.string,
+      value: PropTypes.string,
+      options: PropTypes.oneOfType([PropTypes.array, PropTypes.object]),
+    }) as any,
+    onChange: PropTypes.func,
+    isInline: PropTypes.bool,
+  };
+
+  static serialize = (value: RadiosTypeKnobValue) => value;
+
+  static deserialize = (value: RadiosTypeKnobValue) => value;
+
+  renderRadioButtonList({ options }: RadiosTypeKnobProp) {
     if (Array.isArray(options)) {
       return options.map(val => this.renderRadioButton(val, val));
     }
     return Object.keys(options).map(key => this.renderRadioButton(key, options[key]));
   }
 
-  renderRadioButton(label, value) {
+  renderRadioButton(label: string, value: RadiosTypeKnobValue) {
     const opts = { label, value };
     const { onChange, knob } = this.props;
     const { name } = knob;
@@ -57,23 +99,4 @@ class RadiosType extends Component {
   }
 }
 
-RadiosType.defaultProps = {
-  knob: {},
-  onChange: value => value,
-  isInline: false,
-};
-
-RadiosType.propTypes = {
-  knob: PropTypes.shape({
-    name: PropTypes.string,
-    value: PropTypes.string,
-    options: PropTypes.oneOfType([PropTypes.array, PropTypes.object]),
-  }),
-  onChange: PropTypes.func,
-  isInline: PropTypes.bool,
-};
-
-RadiosType.serialize = value => value;
-RadiosType.deserialize = value => value;
-
 export default RadiosType;
diff --git a/addons/knobs/src/components/types/Select.tsx b/addons/knobs/src/components/types/Select.tsx
index ff3809505ff5..2ecd65caac1a 100644
--- a/addons/knobs/src/components/types/Select.tsx
+++ b/addons/knobs/src/components/types/Select.tsx
@@ -1,9 +1,28 @@
-import React from 'react';
+import React, { FunctionComponent, ChangeEvent } from 'react';
 import PropTypes from 'prop-types';
 
 import { Form } from '@storybook/components';
 
-const SelectType = ({ knob, onChange }) => {
+type SelectTypeKnobValue = string;
+
+interface SelectTypeProps {
+  knob: {
+    name: string;
+    value: SelectTypeKnobValue;
+    options: {
+      [key: string]: SelectTypeKnobValue;
+    };
+  };
+  onChange: (value: SelectTypeKnobValue) => SelectTypeKnobValue;
+}
+
+const serialize = (value: SelectTypeKnobValue) => value;
+const deserialize = (value: SelectTypeKnobValue) => value;
+
+const SelectType: FunctionComponent<SelectTypeProps> & {
+  serialize: typeof serialize;
+  deserialize: typeof deserialize;
+} = ({ knob, onChange }) => {
   const { options } = knob;
   const entries = Array.isArray(options)
     ? options.reduce((acc, k) => Object.assign(acc, { [k]: k }), {})
@@ -15,7 +34,7 @@ const SelectType = ({ knob, onChange }) => {
     <Form.Select
       value={selectedKey}
       name={knob.name}
-      onChange={e => {
+      onChange={(e: ChangeEvent<HTMLSelectElement>) => {
         onChange(entries[e.target.value]);
       }}
       size="flex"
@@ -30,20 +49,21 @@ const SelectType = ({ knob, onChange }) => {
 };
 
 SelectType.defaultProps = {
-  knob: {},
+  knob: {} as any,
   onChange: value => value,
 };
 
 SelectType.propTypes = {
+  // TODO: remove `any` once DefinitelyTyped/DefinitelyTyped#31280 has been resolved
   knob: PropTypes.shape({
     name: PropTypes.string,
     value: PropTypes.any,
     options: PropTypes.oneOfType([PropTypes.array, PropTypes.object]),
-  }),
+  }) as any,
   onChange: PropTypes.func,
 };
 
-SelectType.serialize = value => value;
-SelectType.deserialize = value => value;
+SelectType.serialize = serialize;
+SelectType.deserialize = deserialize;
 
 export default SelectType;
diff --git a/addons/knobs/src/components/types/Text.tsx b/addons/knobs/src/components/types/Text.tsx
index 2f95e8f5b0f0..c07466dc84aa 100644
--- a/addons/knobs/src/components/types/Text.tsx
+++ b/addons/knobs/src/components/types/Text.tsx
@@ -1,16 +1,44 @@
 import PropTypes from 'prop-types';
-import React from 'react';
+import React, { Component, ChangeEvent, WeakValidationMap } from 'react';
 
 import { Form } from '@storybook/components';
 
-class TextType extends React.Component {
-  shouldComponentUpdate(nextProps) {
+type TextTypeKnobValue = string;
+
+interface TextTypeProps {
+  knob: {
+    name: string;
+    value: TextTypeKnobValue;
+  };
+  onChange: (value: TextTypeKnobValue) => TextTypeKnobValue;
+}
+
+export default class TextType extends Component<TextTypeProps> {
+  static defaultProps: TextTypeProps = {
+    knob: {} as any,
+    onChange: value => value,
+  };
+
+  static propTypes: WeakValidationMap<TextTypeProps> = {
+    // TODO: remove `any` once DefinitelyTyped/DefinitelyTyped#31280 has been resolved
+    knob: PropTypes.shape({
+      name: PropTypes.string,
+      value: PropTypes.string,
+    }) as any,
+    onChange: PropTypes.func,
+  };
+
+  static serialize = (value: TextTypeKnobValue) => value;
+
+  static deserialize = (value: TextTypeKnobValue) => value;
+
+  shouldComponentUpdate(nextProps: TextTypeProps) {
     const { knob } = this.props;
 
     return nextProps.knob.value !== knob.value;
   }
 
-  handleChange = event => {
+  handleChange = (event: ChangeEvent<HTMLTextAreaElement>) => {
     const { onChange } = this.props;
     const { value } = event.target;
 
@@ -31,21 +59,3 @@ class TextType extends React.Component {
     );
   }
 }
-
-TextType.defaultProps = {
-  knob: {},
-  onChange: value => value,
-};
-
-TextType.propTypes = {
-  knob: PropTypes.shape({
-    name: PropTypes.string,
-    value: PropTypes.string,
-  }),
-  onChange: PropTypes.func,
-};
-
-TextType.serialize = value => value;
-TextType.deserialize = value => value;
-
-export default TextType;