diff --git a/cms/static/js/spec/views/pages/container_subviews_spec.js b/cms/static/js/spec/views/pages/container_subviews_spec.js
index 8ac10470ed..4f666fce77 100644
--- a/cms/static/js/spec/views/pages/container_subviews_spec.js
+++ b/cms/static/js/spec/views/pages/container_subviews_spec.js
@@ -78,15 +78,16 @@ define(["jquery", "underscore", "underscore.string", "js/common_helpers/ajax_hel
                 respondWithJson(json);
             };
 
-            describe("PreviewActionController", function () {
+            describe("ViewLiveButtonController", function () {
                 var viewPublishedCss = '.button-view',
-                    previewCss = '.button-preview',
                     visibilityNoteCss = '.note-visibility';
 
                 it('renders correctly for unscheduled unit', function () {
                     renderContainerPage(this, mockContainerXBlockHtml);
                     expect(containerPage.$(viewPublishedCss)).toHaveClass(disabledCss);
-                    expect(containerPage.$(previewCss)).not.toHaveClass(disabledCss);
+                    expect(containerPage.$(viewPublishedCss).attr('title')).toBe("Open the courseware in the LMS");
+                    expect(containerPage.$('.button-preview')).not.toHaveClass(disabledCss);
+                    expect(containerPage.$('.button-preview').attr('title')).toBe("Preview the courseware in the LMS");
                 });
 
                 it('updates when publish state changes', function () {
@@ -98,19 +99,6 @@ define(["jquery", "underscore", "underscore.string", "js/common_helpers/ajax_hel
                     expect(containerPage.$(viewPublishedCss)).toHaveClass(disabledCss);
                 });
 
-                it('updates when has_changes attribute changes', function () {
-                    renderContainerPage(this, mockContainerXBlockHtml);
-                    fetch({has_changes: true});
-                    expect(containerPage.$(previewCss)).not.toHaveClass(disabledCss);
-
-                    fetch({published: true, has_changes: false});
-                    expect(containerPage.$(previewCss)).toHaveClass(disabledCss);
-
-                    // If published is false, preview is always enabled.
-                    fetch({published: false, has_changes: false});
-                    expect(containerPage.$(previewCss)).not.toHaveClass(disabledCss);
-                });
-
                 it('updates when has_content_group_components attribute changes', function () {
                     renderContainerPage(this, mockContainerXBlockHtml);
                     fetch({has_content_group_components: false});
diff --git a/cms/static/js/views/pages/container.js b/cms/static/js/views/pages/container.js
index 2b071c2d99..595a3f95e7 100644
--- a/cms/static/js/views/pages/container.js
+++ b/cms/static/js/views/pages/container.js
@@ -68,11 +68,11 @@ define(["jquery", "underscore", "gettext", "js/views/pages/base_page", "js/views
                     });
                     this.publishHistory.render();
 
-                    this.previewActions = new ContainerSubviews.PreviewActionController({
+                    this.viewLiveActions = new ContainerSubviews.ViewLiveButtonController({
                         el: this.$('.nav-actions'),
                         model: this.model
                     });
-                    this.previewActions.render();
+                    this.viewLiveActions.render();
 
                     this.unitOutlineView = new UnitOutlineView({
                         el: this.$('.wrapper-unit-overview'),
diff --git a/cms/static/js/views/pages/container_subviews.js b/cms/static/js/views/pages/container_subviews.js
index 441a4d6860..378e100da4 100644
--- a/cms/static/js/views/pages/container_subviews.js
+++ b/cms/static/js/views/pages/container_subviews.js
@@ -50,28 +50,21 @@ define(["jquery", "underscore", "gettext", "js/views/baseview", "js/views/utils/
         });
 
         /**
-         * A controller for updating the "View Live" and "Preview" buttons.
+         * A controller for updating the "View Live" button.
          */
-        var PreviewActionController = ContainerStateListenerView.extend({
+        var ViewLiveButtonController = ContainerStateListenerView.extend({
             shouldRefresh: function(model) {
-                return ViewUtils.hasChangedAttributes(model, ['has_changes', 'published']);
+                return ViewUtils.hasChangedAttributes(model, ['published']);
             },
 
             render: function() {
-                var previewAction = this.$el.find('.button-preview'),
-                    viewLiveAction = this.$el.find('.button-view');
+                var viewLiveAction = this.$el.find('.button-view');
                 if (this.model.get('published')) {
                     viewLiveAction.removeClass(disabledCss).attr('aria-disabled', false);
                 }
                 else {
                     viewLiveAction.addClass(disabledCss).attr('aria-disabled', true);
                 }
-                if (this.model.get('has_changes') || !this.model.get('published')) {
-                    previewAction.removeClass(disabledCss).attr('aria-disabled', false);
-                }
-                else {
-                    previewAction.addClass(disabledCss).attr('aria-disabled', true);
-                }
             }
         });
 
@@ -256,7 +249,7 @@ define(["jquery", "underscore", "gettext", "js/views/baseview", "js/views/utils/
 
         return {
             'MessageView': MessageView,
-            'PreviewActionController': PreviewActionController,
+            'ViewLiveButtonController': ViewLiveButtonController,
             'Publisher': Publisher,
             'PublishHistory': PublishHistory
         };
diff --git a/cms/templates/container.html b/cms/templates/container.html
index 3fd47ab52c..b93ada88c9 100644
--- a/cms/templates/container.html
+++ b/cms/templates/container.html
@@ -69,13 +69,13 @@ from django.utils.translation import ugettext as _
             <ul>
                 % if is_unit_page:
                     <li class="action-item action-view nav-item">
-                        <a href="${published_preview_link}" class="button button-view action-button is-disabled" aria-disabled="true" rel="external">
+                        <a href="${published_preview_link}" class="button button-view action-button is-disabled" aria-disabled="true" rel="external" title="${_('Open the courseware in the LMS')}">
                             <span class="action-button-text">${_("View Live Version")}</span>
                         </a>
                     </li>
                     <li class="action-item action-preview nav-item">
-                        <a href="${draft_preview_link}" class="button button-preview action-button is-disabled" aria-disabled="true" rel="external">
-                            <span class="action-button-text">${_("Preview Changes")}</span>
+                        <a href="${draft_preview_link}" class="button button-preview action-button" rel="external" title="${_('Preview the courseware in the LMS')}">
+                            <span class="action-button-text">${_("Preview")}</span>
                         </a>
                     </li>
                 % else:
diff --git a/cms/templates/js/mock/mock-container-page.underscore b/cms/templates/js/mock/mock-container-page.underscore
index 6a4474d6bd..d5356605f2 100644
--- a/cms/templates/js/mock/mock-container-page.underscore
+++ b/cms/templates/js/mock/mock-container-page.underscore
@@ -16,13 +16,13 @@
                 <ul>
                     % if is_unit_page:
                         <li class="action-item action-view nav-item">
-                            <a href="${published_preview_link}" class="button button-view action-button is-disabled" aria-disabled="true">
+                            <a href="${published_preview_link}" class="button button-view action-button is-disabled" aria-disabled="true" title="Open the courseware in the LMS">
                                 <span class="action-button-text">View Live Version</span>
                             </a>
                         </li>
                         <li class="action-item action-preview nav-item">
-                            <a href="${draft_preview_link}" class="button button-preview action-button is-disabled" aria-disabled="true">
-                                <span class="action-button-text">Preview Changes</span>
+                            <a href="${draft_preview_link}" class="button button-preview action-button" title="Preview the courseware in the LMS">
+                                <span class="action-button-text">Preview</span>
                             </a>
                         </li>
                     % else:
diff --git a/cms/templates/ux/reference/container.html b/cms/templates/ux/reference/container.html
index 7345641536..81821b503a 100644
--- a/cms/templates/ux/reference/container.html
+++ b/cms/templates/ux/reference/container.html
@@ -46,7 +46,7 @@
                 </li>
                 <li class="action-item action-preview nav-item">
                     <a href="#" class="button preview-button action-button">
-                        <span class="action-button-text">Preview Changes</span>
+                        <span class="action-button-text">Preview</span>
                     </a>
                 </li>
 <!-- end publishing changes -->
diff --git a/common/test/acceptance/pages/studio/container.py b/common/test/acceptance/pages/studio/container.py
index b06b6956be..aa46ce72ca 100644
--- a/common/test/acceptance/pages/studio/container.py
+++ b/common/test/acceptance/pages/studio/container.py
@@ -209,7 +209,7 @@ class ContainerPage(PageObject):
 
     def preview(self):
         """
-        Clicks "Preview Changes", which will open the draft version of the unit page in the LMS.
+        Clicks "Preview", which will open the draft version of the unit page in the LMS.
 
         Switches the browser to the newly opened LMS window.
         """
diff --git a/lms/djangoapps/courseware/access.py b/lms/djangoapps/courseware/access.py
index 759dff19cc..2377335a52 100644
--- a/lms/djangoapps/courseware/access.py
+++ b/lms/djangoapps/courseware/access.py
@@ -22,6 +22,7 @@ from xmodule.error_module import ErrorDescriptor
 from xmodule.x_module import XModule, DEPRECATION_VSCOMPAT_EVENT
 from xmodule.split_test_module import get_split_user_partitions
 from xmodule.partitions.partitions import NoSuchUserPartitionError, NoSuchUserPartitionGroupError
+from xmodule.util.django import get_current_request_hostname
 
 from external_auth.models import ExternalAuthMap
 from courseware.masquerade import get_masquerade_role, is_masquerading_as_student
@@ -436,7 +437,7 @@ def _has_access_descriptor(user, action, descriptor, course_key=None):
                 descriptor,
                 course_key=course_key
             )
-            if now > effective_start:
+            if in_preview_mode() or now > effective_start:
                 # after start date, everyone can see it
                 debug("Allow: now > effective start date")
                 return True
@@ -687,3 +688,11 @@ def get_user_role(user, course_key):
         return 'staff'
     else:
         return 'student'
+
+
+def in_preview_mode():
+    """
+    Returns whether the user is in preview mode or not.
+    """
+    hostname = get_current_request_hostname()
+    return hostname and settings.PREVIEW_DOMAIN in hostname.split('.')
diff --git a/lms/djangoapps/courseware/tests/test_access.py b/lms/djangoapps/courseware/tests/test_access.py
index bf0daeb872..b85fb049fa 100644
--- a/lms/djangoapps/courseware/tests/test_access.py
+++ b/lms/djangoapps/courseware/tests/test_access.py
@@ -42,6 +42,16 @@ class AccessTestCase(LoginEnrollmentTestCase, ModuleStoreTestCase):
         self.course_staff = StaffFactory(course_key=self.course.course_key)
         self.course_instructor = InstructorFactory(course_key=self.course.course_key)
 
+    def verify_access(self, mock_unit, student_should_have_access):
+        """ Verify the expected result from _has_access_descriptor """
+        self.assertEqual(
+            student_should_have_access,
+            access._has_access_descriptor(self.anonymous_user, 'load', mock_unit, course_key=self.course.course_key)
+        )
+        self.assertTrue(
+            access._has_access_descriptor(self.course_staff, 'load', mock_unit, course_key=self.course.course_key)
+        )
+
     def test_has_access_to_course(self):
         self.assertFalse(access._has_access_to_course(
             None, 'staff', self.course.course_key
@@ -132,41 +142,73 @@ class AccessTestCase(LoginEnrollmentTestCase, ModuleStoreTestCase):
         mock_unit = Mock(user_partitions=[])
         mock_unit._class_tags = {}  # Needed for detached check in _has_access_descriptor
 
-        def verify_access(student_should_have_access):
-            """ Verify the expected result from _has_access_descriptor """
-            self.assertEqual(student_should_have_access, access._has_access_descriptor(
-                self.anonymous_user, 'load', mock_unit, course_key=self.course.course_key)
-            )
-            # staff always has access
-            self.assertTrue(access._has_access_descriptor(
-                self.course_staff, 'load', mock_unit, course_key=self.course.course_key)
-            )
-
         # No start date, staff lock on
         mock_unit.visible_to_staff_only = True
-        verify_access(False)
+        self.verify_access(mock_unit, False)
 
         # No start date, staff lock off.
         mock_unit.visible_to_staff_only = False
-        verify_access(True)
+        self.verify_access(mock_unit, True)
 
         # Start date in the past, staff lock on.
         mock_unit.start = datetime.datetime.now(pytz.utc) - datetime.timedelta(days=1)
         mock_unit.visible_to_staff_only = True
-        verify_access(False)
+        self.verify_access(mock_unit, False)
 
         # Start date in the past, staff lock off.
         mock_unit.visible_to_staff_only = False
-        verify_access(True)
+        self.verify_access(mock_unit, True)
 
         # Start date in the future, staff lock on.
         mock_unit.start = datetime.datetime.now(pytz.utc) + datetime.timedelta(days=1)  # release date in the future
         mock_unit.visible_to_staff_only = True
-        verify_access(False)
+        self.verify_access(mock_unit, False)
 
         # Start date in the future, staff lock off.
         mock_unit.visible_to_staff_only = False
-        verify_access(False)
+        self.verify_access(mock_unit, False)
+
+    @patch.dict('django.conf.settings.FEATURES', {'DISABLE_START_DATES': False})
+    @patch('courseware.access.get_current_request_hostname', Mock(return_value='preview.localhost'))
+    def test__has_access_descriptor_in_preview_mode(self):
+        """
+        Tests that descriptor has access in preview mode.
+        """
+        mock_unit = Mock(user_partitions=[])
+        mock_unit._class_tags = {}  # Needed for detached check in _has_access_descriptor
+
+        # No start date.
+        mock_unit.visible_to_staff_only = False
+        self.verify_access(mock_unit, True)
+
+        # Start date in the past.
+        mock_unit.start = datetime.datetime.now(pytz.utc) - datetime.timedelta(days=1)
+        self.verify_access(mock_unit, True)
+
+        # Start date in the future.
+        mock_unit.start = datetime.datetime.now(pytz.utc) + datetime.timedelta(days=1)  # release date in the future
+        self.verify_access(mock_unit, True)
+
+    @patch.dict('django.conf.settings.FEATURES', {'DISABLE_START_DATES': False})
+    @patch('courseware.access.get_current_request_hostname', Mock(return_value='localhost'))
+    def test__has_access_descriptor_when_not_in_preview_mode(self):
+        """
+        Tests that descriptor has no access when start date in future & without preview.
+        """
+        mock_unit = Mock(user_partitions=[])
+        mock_unit._class_tags = {}  # Needed for detached check in _has_access_descriptor
+
+        # No start date.
+        mock_unit.visible_to_staff_only = False
+        self.verify_access(mock_unit, True)
+
+        # Start date in the past.
+        mock_unit.start = datetime.datetime.now(pytz.utc) - datetime.timedelta(days=1)
+        self.verify_access(mock_unit, True)
+
+        # Start date in the future.
+        mock_unit.start = datetime.datetime.now(pytz.utc) + datetime.timedelta(days=1)  # release date in the future
+        self.verify_access(mock_unit, False)
 
     def test__has_access_course_desc_can_enroll(self):
         yesterday = datetime.datetime.now(pytz.utc) - datetime.timedelta(days=1)
diff --git a/lms/djangoapps/courseware/views.py b/lms/djangoapps/courseware/views.py
index a0566fbb7d..fb1c5ba945 100644
--- a/lms/djangoapps/courseware/views.py
+++ b/lms/djangoapps/courseware/views.py
@@ -31,7 +31,7 @@ from django.db import transaction
 from markupsafe import escape
 
 from courseware import grades
-from courseware.access import has_access, _adjust_start_date_for_beta_testers
+from courseware.access import has_access, in_preview_mode, _adjust_start_date_for_beta_testers
 from courseware.courses import (
     get_courses, get_course,
     get_studio_url, get_course_with_access,
@@ -427,7 +427,7 @@ def _index_bulk_op(request, course_key, chapter, section, position):
 
         now = datetime.now(UTC())
         effective_start = _adjust_start_date_for_beta_testers(user, course, course_key)
-        if staff_access and now < effective_start:
+        if not in_preview_mode() and staff_access and now < effective_start:
             # Disable student view button if user is staff and
             # course is not yet visible to students.
             context['disable_student_access'] = True
@@ -702,7 +702,7 @@ def course_info(request, course_id):
 
         now = datetime.now(UTC())
         effective_start = _adjust_start_date_for_beta_testers(request.user, course, course_key)
-        if staff_access and now < effective_start:
+        if not in_preview_mode() and staff_access and now < effective_start:
             # Disable student view button if user is staff and
             # course is not yet visible to students.
             context['disable_student_access'] = True
diff --git a/lms/envs/common.py b/lms/envs/common.py
index 99add8d9b2..7964ce7feb 100644
--- a/lms/envs/common.py
+++ b/lms/envs/common.py
@@ -2295,3 +2295,6 @@ PROFILE_IMAGE_DEFAULT_FILE_EXTENSION = 'png'
 PROFILE_IMAGE_SECRET_KEY = 'placeholder secret key'
 PROFILE_IMAGE_MAX_BYTES = 1024 * 1024
 PROFILE_IMAGE_MIN_BYTES = 100
+
+# This is to check the domain in case of preview.
+PREVIEW_DOMAIN = 'preview'