diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1ff6d511..8dbe7e61 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,11 @@
 All notable changes to the LaunchDarkly client-side JavaScript SDK will be documented in this file. 
 This project adheres to [Semantic Versioning](http://semver.org).
 
+## [1.7.1] - 2018-05-07
+### Fixed
+- The client no longer creates an empty `XMLHttpRequest` at startup time (which could interfere with unit tests).
+- The client now sends the SDK version to LaunchDarkly; previously it only sent the browser version. This will allow for better usage metrics in a future version of the LaunchDarkly UI.
+
 ## [1.7.0] - 2018-04-27
 ### Changed
 - The build now uses Rollup, Babel and Jest.
diff --git a/package.json b/package.json
index a5f54842..be3e2691 100755
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "ldclient-js",
-  "version": "1.7.0",
+  "version": "1.7.1",
   "description": "LaunchDarkly SDK for JavaScript",
   "author": "LaunchDarkly <team@launchdarkly.com>",
   "license": "Apache-2.0",
diff --git a/src/EventProcessor.js b/src/EventProcessor.js
index 137678fb..149f27cc 100644
--- a/src/EventProcessor.js
+++ b/src/EventProcessor.js
@@ -1,17 +1,19 @@
 import * as utils from './utils';
 
 const MAX_URL_LENGTH = 2000;
-const hasCors = 'withCredentials' in new XMLHttpRequest();
 
 function sendEvents(eventsUrl, events, sync) {
   const src = eventsUrl + '?d=' + utils.base64URLEncode(JSON.stringify(events));
 
   const send = onDone => {
+    const xhr = new XMLHttpRequest();
+    const hasCors = 'withCredentials' in xhr;
+
     // Detect browser support for CORS
     if (hasCors) {
       /* supports cross-domain requests */
-      const xhr = new XMLHttpRequest();
       xhr.open('GET', src, !sync);
+      utils.addLDHeaders(xhr);
 
       if (!sync) {
         xhr.addEventListener('load', onDone);
diff --git a/src/Requestor.js b/src/Requestor.js
index b68a92c6..ce2eb00a 100644
--- a/src/Requestor.js
+++ b/src/Requestor.js
@@ -25,9 +25,11 @@ function fetchJSON(endpoint, body, callback) {
   if (body) {
     xhr.open('REPORT', endpoint);
     xhr.setRequestHeader('Content-Type', 'application/json');
+    utils.addLDHeaders(xhr);
     xhr.send(JSON.stringify(body));
   } else {
     xhr.open('GET', endpoint);
+    utils.addLDHeaders(xhr);
     xhr.send();
   }
 
diff --git a/src/__tests__/EventProcessor-test.js b/src/__tests__/EventProcessor-test.js
index 9440cbc7..6ce6457f 100644
--- a/src/__tests__/EventProcessor-test.js
+++ b/src/__tests__/EventProcessor-test.js
@@ -2,6 +2,7 @@ import sinon from 'sinon';
 
 import EventSerializer from '../EventSerializer';
 import EventProcessor from '../EventProcessor';
+import * as utils from '../utils';
 
 describe('EventProcessor', () => {
   let sandbox;
@@ -65,4 +66,15 @@ describe('EventProcessor', () => {
     expect(requests.length).toEqual(1);
     expect(requests[0].async).toEqual(false);
   });
+
+  it('should send custom user-agent header', () => {
+    const processor = EventProcessor('/fake-url', serializer);
+    const user = { key: 'foo' };
+    const event = { kind: 'identify', key: user.key };
+    processor.enqueue(event);
+    processor.flush(user, true);
+
+    expect(requests.length).toEqual(1);
+    expect(requests[0].requestHeaders['X-LaunchDarkly-User-Agent']).toEqual(utils.getLDUserAgentString());
+  });
 });
diff --git a/src/__tests__/Requestor-test.js b/src/__tests__/Requestor-test.js
index 406eb732..c2c0e30d 100644
--- a/src/__tests__/Requestor-test.js
+++ b/src/__tests__/Requestor-test.js
@@ -1,5 +1,6 @@
 import sinon from 'sinon';
 import Requestor from '../Requestor';
+import * as utils from '../utils';
 
 describe('Requestor', () => {
   let server;
@@ -83,4 +84,22 @@ describe('Requestor', () => {
     expect(handleFour.calledOnce).toEqual(true);
     expect(handleFive.calledOnce).toEqual(true);
   });
+
+  it('should send custom user-agent header in GET mode', () => {
+    const requestor = Requestor('http://requestee', 'FAKE_ENV', false);
+    const user = { key: 'foo' };
+    requestor.fetchFlagSettings(user, 'hash1', sinon.spy());
+
+    expect(server.requests.length).toEqual(1);
+    expect(server.requests[0].requestHeaders['X-LaunchDarkly-User-Agent']).toEqual(utils.getLDUserAgentString());
+  });
+
+  it('should send custom user-agent header in REPORT mode', () => {
+    const requestor = Requestor('http://requestee', 'FAKE_ENV', true);
+    const user = { key: 'foo' };
+    requestor.fetchFlagSettings(user, 'hash1', sinon.spy());
+
+    expect(server.requests.length).toEqual(1);
+    expect(server.requests[0].requestHeaders['X-LaunchDarkly-User-Agent']).toEqual(utils.getLDUserAgentString());
+  });
 });
diff --git a/src/utils.js b/src/utils.js
index 2b9f1024..7c8a97a1 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -126,3 +126,11 @@ export function chunkUserEventsForUrl(maxLength, events) {
 
   return allChunks;
 }
+
+export function getLDUserAgentString() {
+  return 'JSClient/' + window.VERSION;
+}
+
+export function addLDHeaders(xhr) {
+  xhr.setRequestHeader('X-LaunchDarkly-User-Agent', getLDUserAgentString());
+}