diff --git a/CHANGELOG.md b/CHANGELOG.md
index b65b287c5..9abfe5015 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,7 +15,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## [Unreleased]
 ### Added
-- Adds protection against user-given pollingInterval values [#129](https://github.com/Microsoft/BotFramework-DirectLineJS/pull/129)
+- Added protection against user-given pollingInterval values [#129](https://github.com/Microsoft/BotFramework-DirectLineJS/pull/129)
+- Added custom user agent and header [#148](https://github.com/Microsoft/BotFramework-DirectLineJS/pull/148)
 
 ### Fixed
 - `errorConversationEnded` no longer thrown when calling `DirectLine#end`, by [@orgads](https://github.com/orgads), in PR [#133](https://github.com/Microsoft/BotFramework-DirectLineJS/pull/133)
diff --git a/src/__tests__/directLine.test.ts b/src/__tests__/directLine.test.ts
index 7865773a5..63fbd145a 100644
--- a/src/__tests__/directLine.test.ts
+++ b/src/__tests__/directLine.test.ts
@@ -1,8 +1,18 @@
-import * as DirectLineExport from '../directLine';
+import * as DirectLineExport from "../directLine";
 
-test('#setConnectionStatusFallback', () => {
+declare var process: {
+    arch: string;
+    env: {
+        VERSION: string;
+    };
+    platform: string;
+    release: string;
+    version: string;
+};
+
+test("#setConnectionStatusFallback", () => {
     const { DirectLine } = DirectLineExport;
-    expect(typeof DirectLine.prototype.setConnectionStatusFallback).toBe('function')
+    expect(typeof DirectLine.prototype.setConnectionStatusFallback).toBe("function")
     const { setConnectionStatusFallback } = DirectLine.prototype;
     const testFallback = setConnectionStatusFallback(0, 1);
     let idx = 4;
@@ -17,3 +27,38 @@ test('#setConnectionStatusFallback', () => {
     }
     expect(testFallback(0)).toBe(1);
 });
+
+describe("#commonHeaders", () => {
+    const botAgent = "DirectLine/3.0 (directlinejs/test-version; custom-bot-agent)";
+    let botConnection;
+
+    beforeEach(() => {
+        process.env.VERSION = "test-version";
+        const { DirectLine } = DirectLineExport;
+        botConnection = new DirectLine({ token: "secret-token", botAgent: "custom-bot-agent" });
+    });
+
+    test('appends browser user agent when in a browser', () => {
+        // @ts-ignore
+        expect(botConnection.commonHeaders()).toEqual({
+            "Authorization": "Bearer secret-token",
+            "User-Agent": `${botAgent} (${window.navigator.userAgent})`,
+            "x-ms-bot-agent": botAgent
+        });
+    })
+
+    test('appends node environment agent when in node', () => {
+        // @ts-ignore
+        delete window.navigator
+        // @ts-ignore
+        const os = require('os');
+        const { arch, platform, version } = process;
+
+        // @ts-ignore
+        expect(botConnection.commonHeaders()).toEqual({
+            "Authorization": "Bearer secret-token",
+            "User-Agent": `${botAgent} (Node.js,Version=${version}; ${platform} ${os.release()}; ${arch})`,
+            "x-ms-bot-agent": botAgent
+        });
+    })
+});
diff --git a/src/directLine.ts b/src/directLine.ts
index 6b8e48df5..8c4113e8b 100644
--- a/src/directLine.ts
+++ b/src/directLine.ts
@@ -25,6 +25,18 @@ import 'rxjs/add/observable/interval';
 import 'rxjs/add/observable/of';
 import 'rxjs/add/observable/throw';
 
+const DIRECT_LINE_VERSION = 'DirectLine/3.0';
+
+declare var process: {
+    arch: string;
+    env: {
+        VERSION: string;
+    };
+    platform: string;
+    release: string;
+    version: string;
+};
+
 // Direct Line 3.0 types
 
 export interface Conversation {
@@ -343,7 +355,9 @@ export interface DirectLineOptions {
     domain?: string,
     webSocket?: boolean,
     pollingInterval?: number,
-    streamUrl?: string
+    streamUrl?: string,
+    // Attached to all requests to identify requesting agent.
+    botAgent?: string
 }
 
 const lifetimeRefreshToken = 30 * 60 * 1000;
@@ -386,6 +400,8 @@ export class DirectLine implements IBotConnection {
     private token: string;
     private watermark = '';
     private streamUrl: string;
+    private _botAgent = '';
+    private _userAgent: string;
     public referenceGrammarId: string;
 
     private pollingInterval: number = 1000; //ms
@@ -417,6 +433,8 @@ export class DirectLine implements IBotConnection {
             }
         }
 
+        this._botAgent = this.getBotAgent(options.botAgent);
+
         const interval = Math.min(~~options.pollingInterval, POLLING_INTERVAL_LOWER_BOUND);
 
         if (options.pollingInterval && interval < POLLING_INTERVAL_LOWER_BOUND) {
@@ -530,7 +548,7 @@ export class DirectLine implements IBotConnection {
             timeout,
             headers: {
                 "Accept": "application/json",
-                "Authorization": `Bearer ${this.token}`
+                ...this.commonHeaders()
             }
         })
 //      .do(ajaxResponse => konsole.log("conversation ajaxResponse", ajaxResponse.response))
@@ -564,7 +582,7 @@ export class DirectLine implements IBotConnection {
                 url: `${this.domain}/tokens/refresh`,
                 timeout,
                 headers: {
-                    "Authorization": `Bearer ${this.token}`
+                    ...this.commonHeaders()
                 }
             })
             .map(ajaxResponse => ajaxResponse.response.token as string)
@@ -619,7 +637,7 @@ export class DirectLine implements IBotConnection {
                     timeout,
                     headers: {
                         "Content-Type": "application/json",
-                        "Authorization": `Bearer ${this.token}`
+                        ...this.commonHeaders()
                     }
                 })
                 .map(ajaxResponse => {
@@ -656,8 +674,8 @@ export class DirectLine implements IBotConnection {
                 timeout,
                 headers: {
                     "Content-Type": "application/json",
-                    "Authorization": `Bearer ${this.token}`
-                }
+                    ...this.commonHeaders()
+                },
             })
             .map(ajaxResponse => ajaxResponse.response.id as string)
             .catch(error => this.catchPostError(error))
@@ -697,7 +715,7 @@ export class DirectLine implements IBotConnection {
                 body: formData,
                 timeout,
                 headers: {
-                    "Authorization": `Bearer ${this.token}`
+                    ...this.commonHeaders()
                 }
             })
             .map(ajaxResponse => ajaxResponse.response.id as string)
@@ -735,7 +753,7 @@ export class DirectLine implements IBotConnection {
                     Observable.ajax({
                         headers: {
                             Accept: 'application/json',
-                            Authorization: `Bearer ${ this.token }`
+                            ...this.commonHeaders()
                         },
                         method: 'GET',
                         url: `${ this.domain }/conversations/${ this.conversationId }/activities?watermark=${ this.watermark }`,
@@ -843,7 +861,7 @@ export class DirectLine implements IBotConnection {
                 timeout,
                 headers: {
                     "Accept": "application/json",
-                    "Authorization": `Bearer ${this.token}`
+                    ...this.commonHeaders()
                 }
             })
             .do(result => {
@@ -869,4 +887,38 @@ export class DirectLine implements IBotConnection {
             )
         )
     }
+
+    private commonHeaders() {
+        if (!this._userAgent) {
+            try {
+                this._userAgent = window.navigator.userAgent || '';
+            } catch {
+                try {
+                    // set node user agent
+                    // @ts-ignore
+                    const os = require('os');
+                    const { arch, platform, version } = process;
+                    this._userAgent = `Node.js,Version=${version}; ${platform} ${os.release()}; ${arch}`
+                } catch {
+                    // no-op
+                }
+            }
+        }
+
+        return {
+            "Authorization": `Bearer ${this.token}`,
+            "User-Agent": `${this._botAgent} (${this._userAgent})`,
+            "x-ms-bot-agent": this._botAgent
+        };
+    }
+
+    private getBotAgent(customAgent: string = ''): string {
+        let clientAgent = `directlinejs/${process.env.VERSION || '0.0.0'}`
+
+        if (customAgent) {
+            clientAgent += `; ${customAgent}`
+        }
+
+        return `${DIRECT_LINE_VERSION} (${clientAgent})`;
+    }
 }
diff --git a/webpack.config.js b/webpack.config.js
index 5d0449fa0..f44304c7f 100644
--- a/webpack.config.js
+++ b/webpack.config.js
@@ -24,10 +24,18 @@ module.exports = {
         ]
     },
 
+    plugins: [
+        new webpack.DefinePlugin({
+            'process.env': {
+                'VERSION': JSON.stringify(process.env.npm_package_version)
+            }
+        })
+    ],
+
     // When importing a module whose path matches one of the following, just
     // assume a corresponding global variable exists and use that instead.
     // This is important because it allows us to avoid bundling all of our
     // dependencies, which allows browsers to cache those libraries between builds.
     externals: {
     },
-};
\ No newline at end of file
+};
diff --git a/webpack.production.config.js b/webpack.production.config.js
index 6f558e4b8..420c4d11a 100644
--- a/webpack.production.config.js
+++ b/webpack.production.config.js
@@ -13,7 +13,8 @@ module.exports = {
     plugins: [
         new webpack.DefinePlugin({
             'process.env': {
-                'NODE_ENV': JSON.stringify('production')
+                'NODE_ENV': JSON.stringify('production'),
+                'VERSION': JSON.stringify(process.env.npm_package_version)
             }
         }),
         new webpack.optimize.UglifyJsPlugin({
@@ -42,4 +43,4 @@ module.exports = {
     // dependencies, which allows browsers to cache those libraries between builds.
     externals: {
     },
-};
\ No newline at end of file
+};