diff --git a/src/language/__tests__/schema-kitchen-sink.graphql b/src/language/__tests__/schema-kitchen-sink.graphql
index be875685df..7e4918d2b6 100644
--- a/src/language/__tests__/schema-kitchen-sink.graphql
+++ b/src/language/__tests__/schema-kitchen-sink.graphql
@@ -36,3 +36,10 @@ input InputType {
 extend type Foo {
   seven(argument: [String]): Type
 }
+
+directive @skip(if: Boolean!) on FIELD | FRAGMENT_SPREAD | INLINE_FRAGMENT
+
+directive @include(if: Boolean!)
+  on FIELD
+   | FRAGMENT_SPREAD
+   | INLINE_FRAGMENT
diff --git a/src/language/__tests__/schema-printer.js b/src/language/__tests__/schema-printer.js
index 50af0b6d55..e2d6bad6f3 100644
--- a/src/language/__tests__/schema-printer.js
+++ b/src/language/__tests__/schema-printer.js
@@ -49,6 +49,7 @@ describe('Printer', () => {
 
     const printed = print(ast);
 
+    /* eslint-disable max-len */
     expect(printed).to.equal(
 `type Foo implements Bar {
   one: Type
@@ -81,6 +82,10 @@ input InputType {
 extend type Foo {
   seven(argument: [String]): Type
 }
+
+directive @skip(if: Boolean!) on FIELD | FRAGMENT_SPREAD | INLINE_FRAGMENT
+
+directive @include(if: Boolean!) on FIELD | FRAGMENT_SPREAD | INLINE_FRAGMENT
 `);
 
   });
diff --git a/src/language/ast.js b/src/language/ast.js
index 90616bc496..f56da99462 100644
--- a/src/language/ast.js
+++ b/src/language/ast.js
@@ -57,6 +57,7 @@ export type Node = Name
                  | EnumValueDefinition
                  | InputObjectTypeDefinition
                  | TypeExtensionDefinition
+                 | DirectiveDefinition
 
 // Name
 
@@ -78,6 +79,7 @@ export type Definition = OperationDefinition
                        | FragmentDefinition
                        | TypeDefinition
                        | TypeExtensionDefinition
+                       | DirectiveDefinition
 
 export type OperationDefinition = {
   kind: 'OperationDefinition';
@@ -332,3 +334,11 @@ export type TypeExtensionDefinition = {
   loc?: ?Location;
   definition: ObjectTypeDefinition;
 }
+
+export type DirectiveDefinition = {
+  kind: 'DirectiveDefinition';
+  loc?: ?Location;
+  name: Name;
+  arguments?: ?Array<InputValueDefinition>;
+  locations: Array<Name>;
+}
diff --git a/src/language/kinds.js b/src/language/kinds.js
index 41d28e8fa5..d586d89088 100644
--- a/src/language/kinds.js
+++ b/src/language/kinds.js
@@ -59,4 +59,11 @@ export const SCALAR_TYPE_DEFINITION = 'ScalarTypeDefinition';
 export const ENUM_TYPE_DEFINITION = 'EnumTypeDefinition';
 export const ENUM_VALUE_DEFINITION = 'EnumValueDefinition';
 export const INPUT_OBJECT_TYPE_DEFINITION = 'InputObjectTypeDefinition';
+
+// Type Extensions
+
 export const TYPE_EXTENSION_DEFINITION = 'TypeExtensionDefinition';
+
+// Directive Definitions
+
+export const DIRECTIVE_DEFINITION = 'DirectiveDefinition';
diff --git a/src/language/parser.js b/src/language/parser.js
index 4aa2230cba..2c406c4e4c 100644
--- a/src/language/parser.js
+++ b/src/language/parser.js
@@ -51,6 +51,8 @@ import type {
   InputObjectTypeDefinition,
 
   TypeExtensionDefinition,
+
+  DirectiveDefinition,
 } from './ast';
 
 import {
@@ -94,6 +96,8 @@ import {
   INPUT_OBJECT_TYPE_DEFINITION,
 
   TYPE_EXTENSION_DEFINITION,
+
+  DIRECTIVE_DEFINITION,
 } from './kinds';
 
 
@@ -205,6 +209,7 @@ function parseDefinition(parser: Parser): Definition {
       case 'enum':
       case 'input': return parseTypeDefinition(parser);
       case 'extend': return parseTypeExtensionDefinition(parser);
+      case 'directive': return parseDirectiveDefinition(parser);
     }
   }
 
@@ -898,6 +903,39 @@ function parseTypeExtensionDefinition(parser: Parser): TypeExtensionDefinition {
   };
 }
 
+/**
+ * DirectiveDefinition :
+ *   - directive @ Name ArgumentsDefinition? on DirectiveLocations
+ */
+function parseDirectiveDefinition(parser: Parser): DirectiveDefinition {
+  const start = parser.token.start;
+  expectKeyword(parser, 'directive');
+  expect(parser, TokenKind.AT);
+  const name = parseName(parser);
+  const args = parseArgumentDefs(parser);
+  expectKeyword(parser, 'on');
+  const locations = parseDirectiveLocations(parser);
+  return {
+    kind: DIRECTIVE_DEFINITION,
+    name,
+    arguments: args,
+    locations,
+    loc: loc(parser, start)
+  };
+}
+
+/**
+ * DirectiveLocations :
+ *   - Name
+ *   - DirectiveLocations | Name
+ */
+function parseDirectiveLocations(parser: Parser): Array<Name> {
+  const locations = [];
+  do {
+    locations.push(parseName(parser));
+  } while (skip(parser, TokenKind.PIPE));
+  return locations;
+}
 
 // Core parsing utility functions
 
diff --git a/src/language/printer.js b/src/language/printer.js
index 977dc1ea77..7edc5d7c6d 100644
--- a/src/language/printer.js
+++ b/src/language/printer.js
@@ -123,6 +123,10 @@ const printDocASTReducer = {
     `input ${name} ${block(fields)}`,
 
   TypeExtensionDefinition: ({ definition }) => `extend ${definition}`,
+
+  DirectiveDefinition: ({ name, arguments: args, locations }) =>
+    'directive @' + name + wrap('(', join(args, ', '), ')') +
+    ' on ' + join(locations, ' | '),
 };
 
 /**
diff --git a/src/language/visitor.js b/src/language/visitor.js
index a49813f64c..3874aa2b04 100644
--- a/src/language/visitor.js
+++ b/src/language/visitor.js
@@ -48,6 +48,7 @@ export const QueryDocumentKeys = {
   EnumValueDefinition: [ 'name' ],
   InputObjectTypeDefinition: [ 'name', 'fields' ],
   TypeExtensionDefinition: [ 'definition' ],
+  DirectiveDefinition: [ 'name', 'arguments', 'locations' ],
 };
 
 export const BREAK = {};
diff --git a/src/type/directives.js b/src/type/directives.js
index b2290604c0..e93adb9674 100644
--- a/src/type/directives.js
+++ b/src/type/directives.js
@@ -8,8 +8,11 @@
  *  of patent rights can be found in the PATENTS file in the same directory.
  */
 
-import { GraphQLNonNull } from './definition';
-import type { GraphQLArgument } from './definition';
+import { isInputType, GraphQLNonNull } from './definition';
+import type {
+  GraphQLFieldConfigArgumentMap,
+  GraphQLArgument
+} from './definition';
 import { GraphQLBoolean } from './scalars';
 import invariant from '../jsutils/invariant';
 import { assertValidName } from '../utilities/assertValidName';
@@ -47,7 +50,31 @@ export class GraphQLDirective {
     this.name = config.name;
     this.description = config.description;
     this.locations = config.locations;
-    this.args = config.args || [];
+
+    const args = config.args;
+    if (!args) {
+      this.args = [];
+    } else {
+      invariant(
+        !Array.isArray(args),
+        `@${config.name} args must be an object with argument names as keys.`
+      );
+      this.args = Object.keys(args).map(argName => {
+        assertValidName(argName);
+        const arg = args[argName];
+        invariant(
+          isInputType(arg.type),
+          `@${config.name}(${argName}:) argument type must be ` +
+          `Input Type but got: ${arg.type}.`
+        );
+        return {
+          name: argName,
+          description: arg.description === undefined ? null : arg.description,
+          type: arg.type,
+          defaultValue: arg.defaultValue === undefined ? null : arg.defaultValue
+        };
+      });
+    }
   }
 }
 
@@ -55,7 +82,7 @@ type GraphQLDirectiveConfig = {
   name: string;
   description?: ?string;
   locations: Array<DirectiveLocationEnum>;
-  args?: ?Array<GraphQLArgument>;
+  args?: ?GraphQLFieldConfigArgumentMap;
 }
 
 /**
@@ -71,11 +98,12 @@ export const GraphQLIncludeDirective = new GraphQLDirective({
     DirectiveLocation.FRAGMENT_SPREAD,
     DirectiveLocation.INLINE_FRAGMENT,
   ],
-  args: [
-    { name: 'if',
+  args: {
+    if: {
       type: new GraphQLNonNull(GraphQLBoolean),
-      description: 'Included when true.' }
-  ],
+      description: 'Included when true.'
+    }
+  },
 });
 
 /**
@@ -91,9 +119,10 @@ export const GraphQLSkipDirective = new GraphQLDirective({
     DirectiveLocation.FRAGMENT_SPREAD,
     DirectiveLocation.INLINE_FRAGMENT,
   ],
-  args: [
-    { name: 'if',
+  args: {
+    if: {
       type: new GraphQLNonNull(GraphQLBoolean),
-      description: 'Skipped when true.' }
-  ],
+      description: 'Skipped when true.'
+    }
+  },
 });
diff --git a/src/utilities/__tests__/buildASTSchema.js b/src/utilities/__tests__/buildASTSchema.js
index 4f6aea1c6b..06e85a3104 100644
--- a/src/utilities/__tests__/buildASTSchema.js
+++ b/src/utilities/__tests__/buildASTSchema.js
@@ -41,6 +41,18 @@ type HelloScalars {
     expect(output).to.equal(body);
   });
 
+  it('With directives', () => {
+    const body = `
+directive @foo(arg: Int) on FIELD
+
+type Hello {
+  str: String
+}
+`;
+    const output = cycleOutput(body, 'Hello');
+    expect(output).to.equal(body);
+  });
+
   it('Type modifiers', () => {
     const body = `
 type HelloScalars {
diff --git a/src/utilities/__tests__/schemaPrinter.js b/src/utilities/__tests__/schemaPrinter.js
index 290cbe83ff..de64fbd1ff 100644
--- a/src/utilities/__tests__/schemaPrinter.js
+++ b/src/utilities/__tests__/schemaPrinter.js
@@ -508,6 +508,10 @@ type Root {
     const Schema = new GraphQLSchema({ query: Root });
     const output = '\n' + printIntrospectionSchema(Schema);
     const introspectionSchema = `
+directive @include(if: Boolean!) on FIELD | FRAGMENT_SPREAD | INLINE_FRAGMENT
+
+directive @skip(if: Boolean!) on FIELD | FRAGMENT_SPREAD | INLINE_FRAGMENT
+
 type __Directive {
   name: String!
   description: String
diff --git a/src/utilities/buildASTSchema.js b/src/utilities/buildASTSchema.js
index fd74a56c0f..0d309c4a9a 100644
--- a/src/utilities/buildASTSchema.js
+++ b/src/utilities/buildASTSchema.js
@@ -25,6 +25,7 @@ import {
   UNION_TYPE_DEFINITION,
   SCALAR_TYPE_DEFINITION,
   INPUT_OBJECT_TYPE_DEFINITION,
+  DIRECTIVE_DEFINITION,
 } from '../language/kinds';
 
 import type {
@@ -39,6 +40,7 @@ import type {
   ScalarTypeDefinition,
   EnumTypeDefinition,
   InputObjectTypeDefinition,
+  DirectiveDefinition,
 } from '../language/ast';
 
 import {
@@ -58,6 +60,8 @@ import {
   GraphQLNonNull,
 } from '../type';
 
+import { GraphQLDirective } from '../type/directives';
+
 import type {
   GraphQLType,
   GraphQLNamedType
@@ -115,6 +119,7 @@ export function buildASTSchema(
   }
 
   const typeDefs: Array<TypeDefinition> = [];
+  const directiveDefs: Array<DirectiveDefinition> = [];
   for (let i = 0; i < ast.definitions.length; i++) {
     const d = ast.definitions[i];
     switch (d.kind) {
@@ -125,6 +130,10 @@ export function buildASTSchema(
       case SCALAR_TYPE_DEFINITION:
       case INPUT_OBJECT_TYPE_DEFINITION:
         typeDefs.push(d);
+        break;
+      case DIRECTIVE_DEFINITION:
+        directiveDefs.push(d);
+        break;
     }
   }
 
@@ -160,13 +169,24 @@ export function buildASTSchema(
 
   typeDefs.forEach(def => typeDefNamed(def.name.value));
 
+  const directives = directiveDefs.map(getDirective);
+
   return new GraphQLSchema({
+    directives,
     query: getObjectType(astMap[queryTypeName]),
     mutation: mutationTypeName ? getObjectType(astMap[mutationTypeName]) : null,
     subscription:
       subscriptionTypeName ? getObjectType(astMap[subscriptionTypeName]) : null,
   });
 
+  function getDirective(directiveAST: DirectiveDefinition): GraphQLDirective {
+    return new GraphQLDirective({
+      name: directiveAST.name.value,
+      locations: directiveAST.locations.map(node => node.value),
+      args: makeInputValues(directiveAST.arguments),
+    });
+  }
+
   function getObjectType(typeAST: TypeDefinition): GraphQLObjectType {
     const type = typeDefNamed(typeAST.name.value);
     invariant(
diff --git a/src/utilities/buildClientSchema.js b/src/utilities/buildClientSchema.js
index 93a07c6697..cb85252b83 100644
--- a/src/utilities/buildClientSchema.js
+++ b/src/utilities/buildClientSchema.js
@@ -342,7 +342,7 @@ export function buildClientSchema(
       name: directiveIntrospection.name,
       description: directiveIntrospection.description,
       locations,
-      args: directiveIntrospection.args.map(buildInputValue),
+      args: buildInputValueDefMap(directiveIntrospection.args),
     });
   }
 
diff --git a/src/utilities/schemaPrinter.js b/src/utilities/schemaPrinter.js
index 854e805f31..3c36eddcf8 100644
--- a/src/utilities/schemaPrinter.js
+++ b/src/utilities/schemaPrinter.js
@@ -25,11 +25,15 @@ import {
 
 
 export function printSchema(schema: GraphQLSchema): string {
-  return printFilteredSchema(schema, isDefinedType);
+  return printFilteredSchema(schema, n => !isSpecDirective(n), isDefinedType);
 }
 
 export function printIntrospectionSchema(schema: GraphQLSchema): string {
-  return printFilteredSchema(schema, isIntrospectionType);
+  return printFilteredSchema(schema, isSpecDirective, isIntrospectionType);
+}
+
+function isSpecDirective(directiveName: string): boolean {
+  return directiveName === 'skip' || directiveName === 'include';
 }
 
 function isDefinedType(typename: string): boolean {
@@ -52,14 +56,19 @@ function isBuiltInScalar(typename: string): boolean {
 
 function printFilteredSchema(
   schema: GraphQLSchema,
+  directiveFilter: (type: string) => boolean,
   typeFilter: (type: string) => boolean
 ): string {
+  const directives = schema.getDirectives()
+    .filter(directive => directiveFilter(directive.name));
   const typeMap = schema.getTypeMap();
   const types = Object.keys(typeMap)
     .filter(typeFilter)
     .sort((name1, name2) => name1.localeCompare(name2))
     .map(typeName => typeMap[typeName]);
-  return types.map(printType).join('\n\n') + '\n';
+  return directives.map(printDirective).concat(
+    types.map(printType)
+  ).join('\n\n') + '\n';
 }
 
 function printType(type: GraphQLType): string {
@@ -124,11 +133,11 @@ function printFields(type) {
   ).join('\n');
 }
 
-function printArgs(field) {
-  if (field.args.length === 0) {
+function printArgs(fieldOrDirectives) {
+  if (fieldOrDirectives.args.length === 0) {
     return '';
   }
-  return '(' + field.args.map(printInputValue).join(', ') + ')';
+  return '(' + fieldOrDirectives.args.map(printInputValue).join(', ') + ')';
 }
 
 function printInputValue(arg) {
@@ -138,3 +147,8 @@ function printInputValue(arg) {
   }
   return argDecl;
 }
+
+function printDirective(directive) {
+  return 'directive @' + directive.name + printArgs(directive) +
+    ' on ' + directive.locations.join(' | ');
+}