diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9ef2552999..747c76eb02 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,16 @@
 # Unreleased
 
+- [changed] Updated the Google Cloud Firestore client to v1.0.1. This contains
+  breaking changes. Refer to Cloud Firestore
+  [release notes](https://github.com/googleapis/nodejs-firestore/releases/tag/v0.20.0)
+  for more details and migration instructions.
+- [changed] Updated the Google Cloud Storage client to v2.3.0. This contains
+  breaking changes. Refer to Cloud Storage
+  [release notes](https://github.com/googleapis/nodejs-storage/releases/tag/v2.0.0)
+  for more details and migration instructions.
+- [changed] `verifyIdToken()` and `verifySessionCookie()` methods now return
+  `auth/id-token-expired` and `auth/session-cookie-expired` error codes for
+  expired JWTs.
 - [fixed] Including additional helpful details in the errors thrown due to
   credentials-related problems.
 
diff --git a/package-lock.json b/package-lock.json
index 2e9a5b4192..9318656611 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -67,95 +67,155 @@
       }
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+      "version": "0.27.0",
+      "resolved": "https://registry.npmjs.org/@google-cloud/common/-/common-0.27.0.tgz",
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       "optional": true,
       "requires": {
-        "array-uniq": "1.0.3",
+        "@google-cloud/projectify": "0.3.2",
+        "@google-cloud/promisify": "0.3.1",
+        "@types/duplexify": "3.6.0",
+        "@types/request": "2.48.1",
         "arrify": "1.0.1",
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         "duplexify": "3.6.1",
         "ent": "2.2.0",
         "extend": "3.0.2",
-        "google-auto-auth": "0.10.1",
+        "google-auth-library": "2.0.1",
+        "pify": "4.0.1",
+        "retry-request": "4.0.0"
+      },
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+        }
+      }
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+    "@google-cloud/firestore": {
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-            "through2": "2.0.5"
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         }
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     },
-    "@google-cloud/firestore": {
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-      "resolved": "https://registry.npmjs.org/@google-cloud/firestore/-/firestore-0.19.0.tgz",
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+    "@google-cloud/paginator": {
+      "version": "0.1.2",
+      "resolved": "https://registry.npmjs.org/@google-cloud/paginator/-/paginator-0.1.2.tgz",
+      "integrity": "sha512-XL09cuPSEPyyNifavxWJRYkUFr5zCJ9njcFjqc1AqSQ2QIKycwdTxOP/zHsAWj0xN3rw1ApevA8o+8VAD4R6hw==",
       "optional": true,
       "requires": {
-        "@google-cloud/projectify": "0.3.2",
-        "bun": "0.0.12",
-        "deep-equal": "1.0.1",
+        "arrify": "1.0.1",
         "extend": "3.0.2",
-        "functional-red-black-tree": "1.0.1",
-        "google-gax": "0.22.1",
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-        "protobufjs": "6.8.8",
-        "through2": "3.0.0"
+        "split-array-stream": "2.0.0",
+        "stream-events": "1.0.5"
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     "@google-cloud/projectify": {
@@ -164,75 +224,37 @@
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+    },
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-      "resolved": "https://registry.npmjs.org/@google-cloud/storage/-/storage-1.7.0.tgz",
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       "optional": true,
       "requires": {
-        "@google-cloud/common": "0.17.0",
+        "@google-cloud/common": "0.27.0",
+        "@google-cloud/paginator": "0.1.2",
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         "hash-stream-validation": "0.2.1",
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         "mime-types": "2.1.21",
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         "stream-events": "1.0.5",
-        "through2": "2.0.5",
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+        "through2": "3.0.0",
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     "@grpc/grpc-js": {
@@ -245,26 +267,6 @@
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-        "lodash": "4.17.11",
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@@ -370,6 +372,15 @@
         "@types/promises-a-plus": "0.0.27"
       }
     },
+    "@types/duplexify": {
+      "version": "3.6.0",
+      "resolved": "https://registry.npmjs.org/@types/duplexify/-/duplexify-3.6.0.tgz",
+      "integrity": "sha512-5zOA53RUlzN74bvrSGwjudssD9F3a797sDZQkiYpUOxW+WHaXTCPz4/d5Dgi6FKnOqZ2CpaTo0DhgIfsXAOE/A==",
+      "optional": true,
+      "requires": {
+        "@types/node": "8.10.38"
+      }
+    },
     "@types/firebase-token-generator": {
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@@ -384,16 +395,6 @@
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@@ -406,7 +407,8 @@
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+      "integrity": "sha512-iiJbKLZbhSa6FYRip/9ZDX6HXhayXLDGY2Fqws9cOkEQ6XeKfaxB0sC541mowZJueYyMnVUmmG+al5/4fCDrgw==",
+      "dev": true
     },
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@@ -500,7 +502,6 @@
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@@ -629,7 +630,8 @@
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-      "integrity": "sha1-r2rId6Jcx/dOBYiUdThY39sk/bY="
+      "integrity": "sha1-r2rId6Jcx/dOBYiUdThY39sk/bY=",
+      "dev": true
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@@ -681,6 +683,7 @@
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-      "resolved": "https://registry.npmjs.org/typescript/-/typescript-2.9.2.tgz",
-      "integrity": "sha512-Gr4p6nFNaoufRIY4NMdpQRNmgxVIGMs4Fcu/ujdYk3nAZqk7supzBE9idmvfZIlH/Cuj//dvi+019qEue9lV0w==",
+      "version": "3.2.2",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-3.2.2.tgz",
+      "integrity": "sha512-VCj5UiSyHBjwfYacmDuc/NOk4QQixbE+Wn7MFJuS0nRuPQbof132Pw4u53dm264O8LPc2MVsc7RJNml5szurkg==",
       "dev": true
     },
     "unc-path-regex": {
diff --git a/package.json b/package.json
index 3613f69d32..760e2587e8 100644
--- a/package.json
+++ b/package.json
@@ -59,9 +59,8 @@
     "node-forge": "0.7.4"
   },
   "optionalDependencies": {
-    "@google-cloud/firestore": "^0.19.0",
-    "@google-cloud/storage": "^1.6.0",
-    "@types/google-cloud__storage": "^1.7.1"
+    "@google-cloud/firestore": "^1.0.1",
+    "@google-cloud/storage": "^2.3.0"
   },
   "devDependencies": {
     "@types/bcrypt": "^2.0.0",
@@ -105,6 +104,6 @@
     "sinon-chai": "^2.8.0",
     "ts-node": "^3.3.0",
     "tslint": "^5.9.0",
-    "typescript": "^2.7.2"
+    "typescript": "^3.1.0"
   }
 }
diff --git a/src/auth/token-verifier.ts b/src/auth/token-verifier.ts
index c63e010232..aac7b31b54 100644
--- a/src/auth/token-verifier.ts
+++ b/src/auth/token-verifier.ts
@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-import {AuthClientErrorCode, FirebaseAuthError} from '../utils/error';
+import {AuthClientErrorCode, FirebaseAuthError, ErrorInfo} from '../utils/error';
 
 import * as validator from '../utils/validator';
 import * as jwt from 'jsonwebtoken';
@@ -38,7 +38,7 @@ export const ID_TOKEN_INFO: FirebaseTokenInfo = {
   verifyApiName: 'verifyIdToken()',
   jwtName: 'Firebase ID token',
   shortName: 'ID token',
-  expiredErrorCode: 'auth/id-token-expired',
+  expiredErrorCode: AuthClientErrorCode.ID_TOKEN_EXPIRED,
 };
 
 /** User facing token information related to the Firebase session cookie. */
@@ -47,7 +47,7 @@ export const SESSION_COOKIE_INFO: FirebaseTokenInfo = {
   verifyApiName: 'verifySessionCookie()',
   jwtName: 'Firebase session cookie',
   shortName: 'session cookie',
-  expiredErrorCode: 'auth/session-cookie-expired',
+  expiredErrorCode: AuthClientErrorCode.SESSION_COOKIE_EXPIRED,
 };
 
 /** Interface that defines token related user facing information. */
@@ -61,7 +61,7 @@ export interface FirebaseTokenInfo {
   /** The JWT short name. */
   shortName: string;
   /** JWT Expiration error code. */
-  expiredErrorCode: string;
+  expiredErrorCode: ErrorInfo;
 }
 
 /**
@@ -115,10 +115,10 @@ export class FirebaseTokenVerifier {
         AuthClientErrorCode.INVALID_ARGUMENT,
         `The JWT public short name must be a non-empty string.`,
       );
-    } else if (!validator.isNonEmptyString(tokenInfo.expiredErrorCode)) {
+    } else if (!validator.isNonNullObject(tokenInfo.expiredErrorCode) || !('code' in tokenInfo.expiredErrorCode)) {
       throw new FirebaseAuthError(
         AuthClientErrorCode.INVALID_ARGUMENT,
-        `The JWT expiration error code must be a non-empty string.`,
+        `The JWT expiration error code must be a non-null ErrorInfo object.`,
       );
     }
     this.shortNameArticle = tokenInfo.shortName.charAt(0).match(/[aeiou]/i) ? 'an' : 'a';
@@ -228,22 +228,23 @@ export class FirebaseTokenVerifier {
    *     verification.
    */
   private verifyJwtSignatureWithKey(jwtToken: string, publicKey: string): Promise<object> {
-    let errorMessage: string;
     const verifyJwtTokenDocsMessage = ` See ${this.tokenInfo.url} ` +
       `for details on how to retrieve ${this.shortNameArticle} ${this.tokenInfo.shortName}.`;
     return new Promise((resolve, reject) => {
       jwt.verify(jwtToken, publicKey, {
         algorithms: [this.algorithm],
-      }, (error: any, decodedToken: any) => {
+      }, (error: jwt.VerifyErrors, decodedToken: any) => {
         if (error) {
           if (error.name === 'TokenExpiredError') {
-            errorMessage = `${this.tokenInfo.jwtName} has expired. Get a fresh token from your client ` +
-              `app and try again (${this.tokenInfo.expiredErrorCode}).` + verifyJwtTokenDocsMessage;
+            const errorMessage = `${this.tokenInfo.jwtName} has expired. Get a fresh ${this.tokenInfo.shortName}` +
+              ` from your client app and try again (auth/${this.tokenInfo.expiredErrorCode.code}).` +
+              verifyJwtTokenDocsMessage;
+            return reject(new FirebaseAuthError(this.tokenInfo.expiredErrorCode, errorMessage));
           } else if (error.name === 'JsonWebTokenError') {
-            errorMessage = `${this.tokenInfo.jwtName} has invalid signature.` + verifyJwtTokenDocsMessage;
+            const errorMessage = `${this.tokenInfo.jwtName} has invalid signature.` + verifyJwtTokenDocsMessage;
+            return reject(new FirebaseAuthError(AuthClientErrorCode.INVALID_ARGUMENT, errorMessage));
           }
-
-          return reject(new FirebaseAuthError(AuthClientErrorCode.INVALID_ARGUMENT, errorMessage));
+          return reject(new FirebaseAuthError(AuthClientErrorCode.INVALID_ARGUMENT, error.message));
         } else {
           decodedToken.uid = decodedToken.sub;
           resolve(decodedToken);
diff --git a/src/storage/storage.ts b/src/storage/storage.ts
index 7c853d91c7..d54bdb2331 100644
--- a/src/storage/storage.ts
+++ b/src/storage/storage.ts
@@ -18,7 +18,7 @@ import {FirebaseApp} from '../firebase-app';
 import {FirebaseError} from '../utils/error';
 import {FirebaseServiceInterface, FirebaseServiceInternalsInterface} from '../firebase-service';
 import {ApplicationDefaultCredential, Certificate} from '../auth/credential';
-import * as gcs from '@google-cloud/storage';
+import {Bucket, Storage as StorageClient} from '@google-cloud/storage';
 
 import * as validator from '../utils/validator';
 
@@ -44,7 +44,7 @@ export class Storage implements FirebaseServiceInterface {
   public readonly INTERNAL: StorageInternals = new StorageInternals();
 
   private readonly appInternal: FirebaseApp;
-  private readonly storageClient: gcs;
+  private readonly storageClient: StorageClient;
 
   /**
    * @param {FirebaseApp} app The app for this Storage service.
@@ -58,9 +58,9 @@ export class Storage implements FirebaseServiceInterface {
       });
     }
 
-    let storage: typeof gcs;
+    let storage: typeof StorageClient;
     try {
-      storage = require('@google-cloud/storage');
+      storage = require('@google-cloud/storage').Storage;
     } catch (err) {
       throw new FirebaseError({
         code: 'storage/missing-dependencies',
@@ -103,7 +103,7 @@ export class Storage implements FirebaseServiceInterface {
    *   retrieves a reference to the default bucket.
    * @return {Bucket} A Bucket object from the @google-cloud/storage library.
    */
-  public bucket(name?: string): gcs.Bucket {
+  public bucket(name?: string): Bucket {
     const bucketName = (typeof name !== 'undefined')
       ? name :  this.appInternal.options.storageBucket;
     if (validator.isNonEmptyString(bucketName)) {
diff --git a/src/utils/error.ts b/src/utils/error.ts
index e149faa13b..e812cd3a2a 100644
--- a/src/utils/error.ts
+++ b/src/utils/error.ts
@@ -542,6 +542,10 @@ export class AuthClientErrorCode {
       'https://firebase.google.com/docs/admin/setup for details on how to authenticate this SDK ' +
       'with appropriate permissions.',
   };
+  public static SESSION_COOKIE_EXPIRED = {
+    code: 'session-cookie-expired',
+    message: 'The Firebase session cookie is expired.',
+  };
   public static SESSION_COOKIE_REVOKED = {
     code: 'session-cookie-revoked',
     message: 'The Firebase session cookie has been revoked.',
diff --git a/test/integration/firestore.spec.ts b/test/integration/firestore.spec.ts
index 021643684e..62a62dd4cd 100644
--- a/test/integration/firestore.spec.ts
+++ b/test/integration/firestore.spec.ts
@@ -35,7 +35,6 @@ describe('admin.firestore', () => {
 
   before(() => {
     const db = admin.firestore();
-    db.settings({timestampsInSnapshots: true});
     reference = db.collection('cities').doc();
   });
 
diff --git a/test/unit/auth/token-verifier.spec.ts b/test/unit/auth/token-verifier.spec.ts
index 573fd18e59..a7f09634f4 100644
--- a/test/unit/auth/token-verifier.spec.ts
+++ b/test/unit/auth/token-verifier.spec.ts
@@ -32,6 +32,7 @@ import {FirebaseTokenGenerator, ServiceAccountSigner} from '../../../src/auth/to
 import * as verifier from '../../../src/auth/token-verifier';
 
 import {Certificate} from '../../../src/auth/credential';
+import { AuthClientErrorCode } from '../../../src/utils/error';
 
 chai.should();
 chai.use(sinonChai);
@@ -39,20 +40,21 @@ chai.use(chaiAsPromised);
 
 const expect = chai.expect;
 
-
 const ONE_HOUR_IN_SECONDS = 60 * 60;
-
+const idTokenPublicCertPath = '/robot/v1/metadata/x509/securetoken@system.gserviceaccount.com';
 
 /**
  * Returns a mocked out success response from the URL containing the public keys for the Google certs.
  *
+ * @param {string=} path URL path to which the mock request should be made. If not specified, defaults
+ *   to the URL path of ID token public key certificates.
  * @return {Object} A nock response object.
  */
-function mockFetchPublicKeys(): nock.Scope {
+function mockFetchPublicKeys(path: string = idTokenPublicCertPath): nock.Scope {
   const mockedResponse: {[key: string]: string} = {};
   mockedResponse[mocks.certificateObject.private_key_id] = mocks.keyPairs[0].public;
   return nock('https://www.googleapis.com')
-    .get('/robot/v1/metadata/x509/securetoken@system.gserviceaccount.com')
+    .get(path)
     .reply(200, mockedResponse, {
       'cache-control': 'public, max-age=1, must-revalidate, no-transform',
     });
@@ -146,7 +148,7 @@ describe('FirebaseTokenVerifier', () => {
             verifyApiName: 'verifyToken()',
             jwtName: 'Important Token',
             shortName: 'token',
-            expiredErrorCode: 'auth/important-token-expired',
+            expiredErrorCode: AuthClientErrorCode.INVALID_ARGUMENT,
           },
        );
       }).not.to.throw();
@@ -208,7 +210,7 @@ describe('FirebaseTokenVerifier', () => {
               verifyApiName: invalidVerifyApiName as any,
               jwtName: 'Important Token',
               shortName: 'token',
-              expiredErrorCode: 'auth/important-token-expired',
+              expiredErrorCode: AuthClientErrorCode.INVALID_ARGUMENT,
             });
         }).to.throw('The JWT verify API name must be a non-empty string.');
       });
@@ -228,7 +230,7 @@ describe('FirebaseTokenVerifier', () => {
               verifyApiName: 'verifyToken()',
               jwtName: invalidJwtName as any,
               shortName: 'token',
-              expiredErrorCode: 'auth/important-token-expired',
+              expiredErrorCode: AuthClientErrorCode.INVALID_ARGUMENT,
             });
         }).to.throw('The JWT public full name must be a non-empty string.');
       });
@@ -248,13 +250,13 @@ describe('FirebaseTokenVerifier', () => {
               verifyApiName: 'verifyToken()',
               jwtName: 'Important Token',
               shortName: invalidShortName as any,
-              expiredErrorCode: 'auth/important-token-expired',
+              expiredErrorCode: AuthClientErrorCode.INVALID_ARGUMENT,
             });
         }).to.throw('The JWT public short name must be a non-empty string.');
       });
     });
 
-    const invalidExpiredErrorCodes = [null, NaN, 0, 1, true, false, [], {}, { a: 1 }, _.noop, ''];
+    const invalidExpiredErrorCodes = [null, NaN, 0, 1, true, false, [], {}, { a: 1 }, _.noop, '', 'test'];
     invalidExpiredErrorCodes.forEach((invalidExpiredErrorCode) => {
       it('should throw given an invalid expiration error code: ' + JSON.stringify(invalidExpiredErrorCode), () => {
         expect(() => {
@@ -270,7 +272,7 @@ describe('FirebaseTokenVerifier', () => {
               shortName: 'token',
               expiredErrorCode: invalidExpiredErrorCode as any,
             });
-        }).to.throw('The JWT expiration error code must be a non-empty string.');
+        }).to.throw('The JWT expiration error code must be a non-null ErrorInfo object.');
       });
     });
   });
@@ -410,8 +412,37 @@ describe('FirebaseTokenVerifier', () => {
 
         // Token should now be invalid
         return tokenVerifier.verifyJWT(mockIdToken)
-          .should.eventually.be.rejectedWith('Firebase ID token has expired. Get a fresh token from your client ' +
-            'app and try again (auth/id-token-expired)');
+          .should.eventually.be.rejectedWith('Firebase ID token has expired. Get a fresh ID token from your client ' +
+            'app and try again (auth/id-token-expired)')
+          .and.have.property('code', 'auth/id-token-expired');
+      });
+    });
+
+    it('should be rejected given an expired Firebase session cookie', () => {
+      const tokenVerifierSessionCookie = new verifier.FirebaseTokenVerifier(
+        'https://www.googleapis.com/identitytoolkit/v3/relyingparty/publicKeys',
+        'RS256',
+        'https://session.firebase.google.com/',
+        'project_id',
+        verifier.SESSION_COOKIE_INFO,
+      );
+      mockedRequests.push(mockFetchPublicKeys('/identitytoolkit/v3/relyingparty/publicKeys'));
+
+      clock = sinon.useFakeTimers(1000);
+
+      const mockSessionCookie = mocks.generateSessionCookie();
+
+      clock.tick((ONE_HOUR_IN_SECONDS * 1000) - 1);
+
+      // Cookie should still be valid
+      return tokenVerifierSessionCookie.verifyJWT(mockSessionCookie).then(() => {
+        clock.tick(1);
+
+        // Cookie should now be invalid
+        return tokenVerifierSessionCookie.verifyJWT(mockSessionCookie)
+          .should.eventually.be.rejectedWith('Firebase session cookie has expired. Get a fresh session cookie from ' +
+            'your client app and try again (auth/session-cookie-expired).')
+          .and.have.property('code', 'auth/session-cookie-expired');
       });
     });