diff --git a/cms/static/coffee/spec/main.coffee b/cms/static/coffee/spec/main.coffee
index 87253d01f1..c5e69aaf24 100644
--- a/cms/static/coffee/spec/main.coffee
+++ b/cms/static/coffee/spec/main.coffee
@@ -283,6 +283,8 @@ while i < testFiles.length
     testFiles[i] = '/base/' + testFiles[i] + '.js'
     i++
 
-require testFiles, ->
+# Jasmine has a global stack for creating a tree of specs. We need to load
+# spec files one by one, otherwise some end up getting nested under others.
+requireSerial testFiles, ->
 # start test run, once Require.js is done
     window.__karma__.start()
diff --git a/cms/static/coffee/spec/main_squire.coffee b/cms/static/coffee/spec/main_squire.coffee
index e2ab5fc35d..a3480f3516 100644
--- a/cms/static/coffee/spec/main_squire.coffee
+++ b/cms/static/coffee/spec/main_squire.coffee
@@ -202,6 +202,9 @@ i = 0
 while i < testFiles.length
     testFiles[i] = '/base/' + testFiles[i] + '.js'
     i++
-require testFiles, ->
+
+# Jasmine has a global stack for creating a tree of specs. We need to load
+# spec files one by one, otherwise some end up getting nested under others.
+requireSerial testFiles, ->
 # start test run, once Require.js is done
     window.__karma__.start()
diff --git a/cms/static/js/spec/views/xblock_spec.js b/cms/static/js/spec/views/xblock_spec.js
index bcbfabfffa..9777008f05 100644
--- a/cms/static/js/spec/views/xblock_spec.js
+++ b/cms/static/js/spec/views/xblock_spec.js
@@ -62,8 +62,8 @@ define(["jquery", "URI", "common/js/spec_helpers/ajax_helpers", "common/js/compo
                         mockCssUrl = "mock.css",
                         headHtml;
                     postXBlockRequest(requests, [
-                        ["hash1", { mimetype: "text/css", kind: "text", data: mockCssText }],
-                        ["hash2", { mimetype: "text/css", kind: "url", data: mockCssUrl }]
+                        ["xblock_spec_hash1", { mimetype: "text/css", kind: "text", data: mockCssText }],
+                        ["xblock_spec_hash2", { mimetype: "text/css", kind: "url", data: mockCssUrl }]
                     ]);
                     headHtml = $('head').html();
                     expect(headHtml).toContain(mockCssText);
@@ -73,7 +73,9 @@ define(["jquery", "URI", "common/js/spec_helpers/ajax_helpers", "common/js/compo
                 it('can render an xblock with required JavaScript', function() {
                     var requests = AjaxHelpers.requests(this);
                     postXBlockRequest(requests, [
-                        ["hash3", { mimetype: "application/javascript", kind: "text", data: "window.test = 100;" }]
+                        ["xblock_spec_hash3", {
+                            mimetype: "application/javascript", kind: "text", data: "window.test = 100;"
+                        }]
                     ]);
                     expect(window.test).toBe(100);
                 });
@@ -82,7 +84,7 @@ define(["jquery", "URI", "common/js/spec_helpers/ajax_helpers", "common/js/compo
                     var requests = AjaxHelpers.requests(this),
                         mockHeadTag = "<title>Test Title</title>";
                     postXBlockRequest(requests, [
-                        ["hash4", { mimetype: "text/html", placement: "head", data: mockHeadTag }]
+                        ["xblock_spec_hash4", { mimetype: "text/html", placement: "head", data: mockHeadTag }]
                     ]);
                     expect($('head').html()).toContain(mockHeadTag);
                 });
@@ -93,7 +95,9 @@ define(["jquery", "URI", "common/js/spec_helpers/ajax_helpers", "common/js/compo
                         promise;
                     spyOn(ViewUtils, 'loadJavaScript').and.returnValue($.Deferred().reject().promise());
                     promise = postXBlockRequest(requests, [
-                        ["hash5", { mimetype: "application/javascript", kind: "url", data: missingJavaScriptUrl }]
+                        ["xblock_spec_hash5", {
+                            mimetype: "application/javascript", kind: "url", data: missingJavaScriptUrl
+                        }]
                     ]);
                     expect(promise.isRejected()).toBe(true);
                 });
diff --git a/cms/static/karma_cms.conf.js b/cms/static/karma_cms.conf.js
index b315e2e962..a33692da00 100644
--- a/cms/static/karma_cms.conf.js
+++ b/cms/static/karma_cms.conf.js
@@ -82,7 +82,9 @@ var libraryFiles = [
     {pattern: 'edx-pattern-library/js/afontgarde.js', included: false},
     {pattern: 'edx-pattern-library/js/edx-icons.js', included: false},
     {pattern: 'edx-pattern-library/js/**/*.js', included: false},
-    {pattern: 'edx-ui-toolkit/js/**/*.js', included: false}
+    {pattern: 'edx-ui-toolkit/js/**/*.js', included: false},
+
+    {pattern: 'common/js/utils/require-serial.js', included: true}
 ];
 
 // Paths to source JavaScript files
diff --git a/cms/static/karma_cms_squire.conf.js b/cms/static/karma_cms_squire.conf.js
index 7d6ec26748..bf6756dd57 100644
--- a/cms/static/karma_cms_squire.conf.js
+++ b/cms/static/karma_cms_squire.conf.js
@@ -68,7 +68,8 @@ var libraryFiles = [
         pattern: 'xmodule_js/common_static/js/vendor/jQuery-File-Upload/js/jquery.fileupload-validate.js',
         included: false
     },
-    {pattern: 'xmodule_js/common_static/js/vendor/requirejs/text.js', included: false}
+    {pattern: 'xmodule_js/common_static/js/vendor/requirejs/text.js', included: false},
+    {pattern: 'common/js/utils/require-serial.js', included: true}
 ];
 
 // Paths to source JavaScript files
diff --git a/common/static/common/js/spec/main_requirejs.js b/common/static/common/js/spec/main_requirejs.js
index eebe0a92b0..c859348826 100644
--- a/common/static/common/js/spec/main_requirejs.js
+++ b/common/static/common/js/spec/main_requirejs.js
@@ -178,7 +178,7 @@
         testFiles[i] = '/base/' + testFiles[i];
     }
 
-    require(testFiles, function () {
+    window.requireSerial(testFiles, function () {
         // start test run, once Require.js is done
         window.__karma__.start();
     });
diff --git a/common/static/common/js/utils/require-serial.js b/common/static/common/js/utils/require-serial.js
new file mode 100644
index 0000000000..c55b6bd628
--- /dev/null
+++ b/common/static/common/js/utils/require-serial.js
@@ -0,0 +1,23 @@
+/*
+Helper function used to require files serially instead of concurrently.
+ */
+(function (window, require) {
+  'use strict';
+
+  var requireModules = function (paths, callback, modules) {
+      // If all the modules have been loaded, call the callback.
+      if (paths.length === 0) {
+        return callback.apply(null, modules);
+      }
+      // Otherwise load the next one.
+      require([paths.shift()], function(module) {
+        modules.push(module);
+        requireModules(paths, callback, modules);
+      });
+  };
+
+  window.requireSerial = function(paths, callback) {
+    requireModules(paths, callback, []);
+  };
+
+}).call(this, window, require || RequireJS.require);
diff --git a/common/static/karma_common_requirejs.conf.js b/common/static/karma_common_requirejs.conf.js
index 475d869d3c..7590ff4694 100644
--- a/common/static/karma_common_requirejs.conf.js
+++ b/common/static/karma_common_requirejs.conf.js
@@ -46,7 +46,8 @@ var libraryFiles = [
     {pattern: 'js/test/i18n.js', included: false},
     {pattern: 'coffee/src/jquery.immediateDescendents.js', included: false},
     {pattern: 'js/vendor/requirejs/text.js', included: false},
-    {pattern: 'js/vendor/sinon-1.17.0.js', included: false}
+    {pattern: 'js/vendor/sinon-1.17.0.js', included: false},
+    {pattern: 'common/js/utils/require-serial.js', included: true}
 ];
 
 // Paths to source JavaScript files
diff --git a/lms/djangoapps/teams/static/teams/js/spec/teams_tab_factory_spec.js b/lms/djangoapps/teams/static/teams/js/spec/teams_tab_factory_spec.js
index d41cfce9d5..de6b4e104b 100644
--- a/lms/djangoapps/teams/static/teams/js/spec/teams_tab_factory_spec.js
+++ b/lms/djangoapps/teams/static/teams/js/spec/teams_tab_factory_spec.js
@@ -1,6 +1,6 @@
-define(['jquery', 'backbone', 'teams/js/teams_tab_factory',
+define(['jquery', 'backbone', 'teams/js/teams_tab_factory', 'teams/js/views/teams_tab',
         'common/js/spec_helpers/page_helpers', 'teams/js/spec_helpers/team_spec_helpers'],
-    function($, Backbone, TeamsTabFactory, PageHelpers, TeamSpecHelpers) {
+    function($, Backbone, TeamsTabFactory, TeamsTabView, PageHelpers, TeamSpecHelpers) {
         'use strict';
 
         describe("Teams Tab Factory", function() {
@@ -15,6 +15,7 @@ define(['jquery', 'backbone', 'teams/js/teams_tab_factory',
 
             afterEach(function() {
                 Backbone.history.stop();
+                $(document).off('ajaxError', TeamsTabView.prototype.errorHandler);
             });
 
             it('can render the "Teams" tab', function() {
diff --git a/lms/djangoapps/teams/static/teams/js/spec/views/teams_tab_spec.js b/lms/djangoapps/teams/static/teams/js/spec/views/teams_tab_spec.js
index e9f58659dd..2f236433e1 100644
--- a/lms/djangoapps/teams/static/teams/js/spec/views/teams_tab_spec.js
+++ b/lms/djangoapps/teams/static/teams/js/spec/views/teams_tab_spec.js
@@ -56,7 +56,11 @@ define([
             spyOn(Logger, 'log');
         });
 
-        afterEach(Backbone.history.stop);
+        afterEach(function() {
+              Backbone.history.stop();
+              $(document).off('ajaxError', TeamsTabView.prototype.errorHandler);
+          }
+        );
 
         describe('Navigation', function () {
             it('does not render breadcrumbs for the top level tabs', function() {
diff --git a/lms/djangoapps/teams/static/teams/js/views/teams_tab.js b/lms/djangoapps/teams/static/teams/js/views/teams_tab.js
index 7aadb4fed2..69e5241213 100644
--- a/lms/djangoapps/teams/static/teams/js/views/teams_tab.js
+++ b/lms/djangoapps/teams/static/teams/js/views/teams_tab.js
@@ -159,14 +159,7 @@
                 start: function() {
                     Backbone.history.start();
 
-                    $(document).ajaxError(function (event, xhr) {
-                        if (xhr.status === 401) {
-                            TeamUtils.showMessage(gettext("Your request could not be completed. Reload the page and try again."));
-                        }
-                        else if (xhr.status === 500) {
-                            TeamUtils.showMessage(gettext("Your request could not be completed due to a server problem. Reload the page and try again. If the issue persists, click the Help tab to report the problem."));
-                        }
-                    });
+                    $(document).ajaxError(this.errorHandler);
 
                     // Navigate to the default page if there is no history:
                     // 1. If the user belongs to at least one team, jump to the "My Teams" page
@@ -180,6 +173,20 @@
                     }
                 },
 
+                errorHandler: function(event, xhr) {
+                    if (xhr.status === 401) {
+                        TeamUtils.showMessage(gettext(
+                            "Your request could not be completed. Reload the page and try again."
+                        ));
+                    }
+                    else if (xhr.status === 500) {
+                        TeamUtils.showMessage(gettext(
+                            "Your request could not be completed due to a server problem. Reload the page" +
+                            " and try again. If the issue persists, click the Help tab to report the problem."
+                        ));
+                    }
+                },
+
                 render: function() {
                     this.mainView.setElement(this.$el).render();
                     TeamUtils.hideMessage();
diff --git a/lms/static/js/spec/main.js b/lms/static/js/spec/main.js
index 2439da0eb8..6bc5f9f481 100644
--- a/lms/static/js/spec/main.js
+++ b/lms/static/js/spec/main.js
@@ -770,7 +770,9 @@
         testFiles[i] = '/base/' + testFiles[i];
     }
 
-    require(testFiles, function () {
+    // Jasmine has a global stack for creating a tree of specs. We need to load
+    // spec files one by one, otherwise some end up getting nested under others.
+    window.requireSerial(testFiles, function () {
         // start test run, once Require.js is done
         window.__karma__.start();
     });
diff --git a/lms/static/karma_lms.conf.js b/lms/static/karma_lms.conf.js
index 9f8efa3caa..10634dd8da 100644
--- a/lms/static/karma_lms.conf.js
+++ b/lms/static/karma_lms.conf.js
@@ -73,7 +73,8 @@ var libraryFiles = [
     {pattern: 'xmodule_js/common_static/js/vendor/slick.core.js', included: true},
     {pattern: 'xmodule_js/common_static/js/vendor/slick.grid.js', included: true},
     {pattern: 'xmodule_js/common_static/js/libs/jasmine-waituntil.js', included: true},
-    {pattern: 'xmodule_js/common_static/js/libs/jasmine-extensions.js', included: true}
+    {pattern: 'xmodule_js/common_static/js/libs/jasmine-extensions.js', included: true},
+    {pattern: 'common/js/utils/require-serial.js', included: true}
 ];
 
 // Paths to source JavaScript files