diff --git a/app/assets/javascripts/issuable_context.js b/app/assets/javascripts/issuable_context.js
index 566efa0d7d63ac66e94a9dc7cc2fcc6d36213959..6f2bd2da07813daf4d336587df6160ed9ebc3137 100644
--- a/app/assets/javascripts/issuable_context.js
+++ b/app/assets/javascripts/issuable_context.js
@@ -6,6 +6,7 @@ import UsersSelect from './users_select';
 export default class IssuableContext {
   constructor(currentUser) {
     this.userSelect = new UsersSelect(currentUser);
+    this.reviewersSelect = new UsersSelect(currentUser, '.js-reviewer-search');
 
     import(/* webpackChunkName: 'select2' */ 'select2/select2')
       .then(() => {
diff --git a/app/assets/javascripts/sidebar/sidebar_mediator.js b/app/assets/javascripts/sidebar/sidebar_mediator.js
index 8f1f76a2e02af00412fa329b63843e597f612183..2146fb83b1364c027a909c13427431fca2630452 100644
--- a/app/assets/javascripts/sidebar/sidebar_mediator.js
+++ b/app/assets/javascripts/sidebar/sidebar_mediator.js
@@ -40,6 +40,17 @@ export default class SidebarMediator {
     return this.service.update(field, data);
   }
 
+  saveReviewers(field) {
+    const selected = this.store.reviewers.map(u => u.id);
+
+    // If there are no ids, that means we have to unassign (which is id = 0)
+    // And it only accepts an array, hence [0]
+    const reviewers = selected.length === 0 ? [0] : selected;
+    const data = { reviewer_ids: reviewers };
+
+    return this.service.update(field, data);
+  }
+
   setMoveToProjectId(projectId) {
     this.store.setMoveToProjectId(projectId);
   }
@@ -55,6 +66,7 @@ export default class SidebarMediator {
 
   processFetchedData(data) {
     this.store.setAssigneeData(data);
+    this.store.setReviewerData(data);
     this.store.setTimeTrackingData(data);
     this.store.setParticipantsData(data);
     this.store.setSubscriptionsData(data);
diff --git a/app/assets/javascripts/sidebar/stores/sidebar_store.js b/app/assets/javascripts/sidebar/stores/sidebar_store.js
index 095f93b72a9f0dccacd16a4573c9caaa9030da98..8d0d093e920fceb586a7bf92c64ea6b877356211 100644
--- a/app/assets/javascripts/sidebar/stores/sidebar_store.js
+++ b/app/assets/javascripts/sidebar/stores/sidebar_store.js
@@ -18,8 +18,10 @@ export default class SidebarStore {
     this.humanTimeSpent = '';
     this.timeTrackingLimitToHours = timeTrackingLimitToHours;
     this.assignees = [];
+    this.reviewers = [];
     this.isFetching = {
       assignees: true,
+      reviewers: true,
       participants: true,
       subscriptions: true,
     };
@@ -42,6 +44,13 @@ export default class SidebarStore {
     }
   }
 
+  setReviewerData(data) {
+    this.isFetching.reviewers = false;
+    if (data.reviewers) {
+      this.reviewers = data.reviewers;
+    }
+  }
+
   setTimeTrackingData(data) {
     this.timeEstimate = data.time_estimate;
     this.totalTimeSpent = data.total_time_spent;
@@ -75,20 +84,40 @@ export default class SidebarStore {
     }
   }
 
+  addReviewer(reviewer) {
+    if (!this.findReviewer(reviewer)) {
+      this.reviewers.push(reviewer);
+    }
+  }
+
   findAssignee(findAssignee) {
     return this.assignees.find(assignee => assignee.id === findAssignee.id);
   }
 
+  findReviewer(findReviewer) {
+    return this.reviewers.find(reviewer => reviewer.id === findReviewer.id);
+  }
+
   removeAssignee(removeAssignee) {
     if (removeAssignee) {
       this.assignees = this.assignees.filter(assignee => assignee.id !== removeAssignee.id);
     }
   }
 
+  removeReviewer(removeReviewer) {
+    if (removeReviewer) {
+      this.reviewers = this.reviewers.filter(reviewer => reviewer.id !== removeReviewer.id);
+    }
+  }
+
   removeAllAssignees() {
     this.assignees = [];
   }
 
+  removeAllReviewers() {
+    this.reviewers = [];
+  }
+
   setAssigneesFromRealtime(data) {
     this.assignees = data;
   }
diff --git a/app/assets/javascripts/users_select/index.js b/app/assets/javascripts/users_select/index.js
index 5f4260f26ff4cd6d73fd090ec93725335479be12..20d1a3c1fcd535d65f7a06c4eda63882340392ce 100644
--- a/app/assets/javascripts/users_select/index.js
+++ b/app/assets/javascripts/users_select/index.js
@@ -19,6 +19,7 @@ import initDeprecatedJQueryDropdown from '~/deprecated_jquery_dropdown';
 window.emitSidebarEvent = window.emitSidebarEvent || $.noop;
 
 function UsersSelect(currentUser, els, options = {}) {
+  const elsClassName = els?.toString().match('.(.+$)')[1];
   const $els = $(els || '.js-user-search');
   this.users = this.users.bind(this);
   this.user = this.user.bind(this);
@@ -127,9 +128,16 @@ function UsersSelect(currentUser, els, options = {}) {
             .find(`input[name='${$dropdown.data('fieldName')}'][value=${firstSelectedId}]`);
 
           firstSelected.remove();
-          emitSidebarEvent('sidebar.removeAssignee', {
-            id: firstSelectedId,
-          });
+
+          if ($dropdown.hasClass(elsClassName)) {
+            emitSidebarEvent('sidebar.removeReviewer', {
+              id: firstSelectedId,
+            });
+          } else {
+            emitSidebarEvent('sidebar.removeAssignee', {
+              id: firstSelectedId,
+            });
+          }
         }
       }
     };
@@ -392,7 +400,11 @@ function UsersSelect(currentUser, els, options = {}) {
       defaultLabel,
       hidden() {
         if ($dropdown.hasClass('js-multiselect')) {
-          emitSidebarEvent('sidebar.saveAssignees');
+          if ($dropdown.hasClass(elsClassName)) {
+            emitSidebarEvent('sidebar.saveReviewers');
+          } else {
+            emitSidebarEvent('sidebar.saveAssignees');
+          }
         }
 
         if (!$dropdown.data('alwaysShowSelectbox')) {
@@ -428,10 +440,18 @@ function UsersSelect(currentUser, els, options = {}) {
             previouslySelected.each((index, element) => {
               element.remove();
             });
-            emitSidebarEvent('sidebar.removeAllAssignees');
+            if ($dropdown.hasClass(elsClassName)) {
+              emitSidebarEvent('sidebar.removeAllReviewers');
+            } else {
+              emitSidebarEvent('sidebar.removeAllAssignees');
+            }
           } else if (isActive) {
             // user selected
-            emitSidebarEvent('sidebar.addAssignee', user);
+            if ($dropdown.hasClass(elsClassName)) {
+              emitSidebarEvent('sidebar.addReviewer', user);
+            } else {
+              emitSidebarEvent('sidebar.addAssignee', user);
+            }
 
             // Remove unassigned selection (if it was previously selected)
             const unassignedSelected = $dropdown
@@ -448,7 +468,11 @@ function UsersSelect(currentUser, els, options = {}) {
             }
 
             // User unselected
-            emitSidebarEvent('sidebar.removeAssignee', user);
+            if ($dropdown.hasClass(elsClassName)) {
+              emitSidebarEvent('sidebar.removeReviewer', user);
+            } else {
+              emitSidebarEvent('sidebar.removeAssignee', user);
+            }
           }
 
           if (getSelected().find(u => u === gon.current_user_id)) {
diff --git a/app/helpers/issuables_helper.rb b/app/helpers/issuables_helper.rb
index b255597b18d6e2d2c29f029f924a629abadb810e..c85f2ceb82e1bcbc2f73ddbb14aad15376ca1821 100644
--- a/app/helpers/issuables_helper.rb
+++ b/app/helpers/issuables_helper.rb
@@ -386,6 +386,12 @@ def assignee_sidebar_data(assignee, merge_request: nil)
     end
   end
 
+  def reviewer_sidebar_data(reviewer, merge_request: nil)
+    { avatar_url: reviewer.avatar_url, name: reviewer.name, username: reviewer.username }.tap do |data|
+      data[:can_merge] = merge_request.can_be_merged_by?(reviewer) if merge_request
+    end
+  end
+
   def issuable_squash_option?(issuable, project)
     if issuable.persisted?
       issuable.squash
diff --git a/app/views/projects/merge_requests/show.html.haml b/app/views/projects/merge_requests/show.html.haml
index b579f7510f9b33f2c42273498c0d49b46313d358..9a3078991c0b3aa7a47c609d620cb1234863e13b 100644
--- a/app/views/projects/merge_requests/show.html.haml
+++ b/app/views/projects/merge_requests/show.html.haml
@@ -92,7 +92,7 @@
       .loading.hide
         .spinner.spinner-md
 
-= render 'shared/issuable/sidebar', issuable_sidebar: @issuable_sidebar, assignees: @merge_request.assignees, source_branch: @merge_request.source_branch
+= render 'shared/issuable/sidebar', issuable_sidebar: @issuable_sidebar, assignees: @merge_request.assignees, reviewers: @merge_request.reviewers, source_branch: @merge_request.source_branch
 
 - if @merge_request.can_be_reverted?(current_user)
   = render "projects/commit/change", type: 'revert', commit: @merge_request.merge_commit, title: @merge_request.title
diff --git a/app/views/shared/issuable/_sidebar.html.haml b/app/views/shared/issuable/_sidebar.html.haml
index 09ec49a040a1d178e804422bdd51a83fd7bd8648..86484239546fed9750d91693bc0360a8e4ba633d 100644
--- a/app/views/shared/issuable/_sidebar.html.haml
+++ b/app/views/shared/issuable/_sidebar.html.haml
@@ -5,6 +5,7 @@
 - signed_in = !!issuable_sidebar.dig(:current_user, :id)
 - can_edit_issuable = issuable_sidebar.dig(:current_user, :can_edit)
 - add_page_startup_api_call "#{issuable_sidebar[:issuable_json_path]}?serializer=sidebar_extras"
+- reviewers = local_assigns.fetch(:reviewers, nil)
 
 - if Feature.enabled?(:vue_issuable_sidebar, @project.group)
   %aside#js-vue-issuable-sidebar{ data: { signed_in: signed_in,
@@ -28,6 +29,10 @@
         .block.assignee.qa-assignee-block
           = render "shared/issuable/sidebar_assignees", issuable_sidebar: issuable_sidebar, assignees: assignees
 
+        - if reviewers
+          .block.reviewer.qa-reviewer-block
+            = render "shared/issuable/sidebar_reviewers", issuable_sidebar: issuable_sidebar, reviewers: reviewers
+
         = render_if_exists 'shared/issuable/sidebar_item_epic', issuable_sidebar: issuable_sidebar
 
         - if issuable_sidebar[:supports_milestone]
diff --git a/app/views/shared/issuable/_sidebar_reviewers.html.haml b/app/views/shared/issuable/_sidebar_reviewers.html.haml
new file mode 100644
index 0000000000000000000000000000000000000000..8b546d5e3445ec5715acd84dbe712b58c3e71597
--- /dev/null
+++ b/app/views/shared/issuable/_sidebar_reviewers.html.haml
@@ -0,0 +1,56 @@
+- issuable_type = issuable_sidebar[:type]
+- signed_in = !!issuable_sidebar.dig(:current_user, :id)
+
+#js-vue-sidebar-reviewers{ data: { field: issuable_type, signed_in: signed_in } }
+  .title.hide-collapsed
+    = _('Reviewer')
+    = loading_icon(css_class: 'gl-vertical-align-text-bottom')
+
+.selectbox.hide-collapsed
+  - if reviewers.none?
+    = hidden_field_tag "#{issuable_type}[reviewer_ids][]", 0, id: nil
+  - else
+    - reviewers.each do |reviewer|
+      = hidden_field_tag "#{issuable_type}[reviewer_ids][]", reviewer.id, id: nil, data: reviewer_sidebar_data(reviewer, merge_request: @merge_request)
+
+  - options = { toggle_class: 'js-reviewer-search js-author-search',
+    title: _('Request review from'),
+    filter: true,
+    dropdown_class: 'dropdown-menu-user dropdown-menu-selectable dropdown-menu-author',
+    placeholder: _('Search users'),
+    data: { first_user: issuable_sidebar.dig(:current_user, :username),
+      current_user: true,
+      iid: issuable_sidebar[:iid],
+      issuable_type: issuable_type,
+      project_id: issuable_sidebar[:project_id],
+      author_id: issuable_sidebar[:author_id],
+      field_name: "#{issuable_type}[reviewer_ids][]",
+      issue_update: issuable_sidebar[:issuable_json_path],
+      ability_name: issuable_type,
+      null_user: true,
+      display: 'static' } }
+
+  - dropdown_options = reviewers_dropdown_options(issuable_type)
+  - title = dropdown_options[:title]
+  - options[:toggle_class] += ' js-multiselect js-save-user-data'
+  - data = { field_name: "#{issuable_type}[reviewer_ids][]" }
+  - data[:multi_select] = true
+  - data['dropdown-title'] = title
+  - data['dropdown-header'] = dropdown_options[:data][:'dropdown-header']
+  - data['max-select'] = dropdown_options[:data][:'max-select'] if dropdown_options[:data][:'max-select']
+  - options[:data].merge!(data)
+
+  - if experiment_enabled?(:invite_members_version_a) && can_import_members?
+    - options[:dropdown_class] += ' dropdown-extended-height'
+    - options[:footer_content] = true
+    - options[:wrapper_class] = 'js-sidebar-reviewer-dropdown'
+
+    = dropdown_tag(title, options: options) do
+      %ul.dropdown-footer-list
+        %li
+          = link_to _('Invite Members'),
+            project_project_members_path(@project),
+            title: _('Invite Members'),
+            data: { 'is-link': true, 'track-event': 'click_invite_members', 'track-label': 'edit_reviewer' }
+  - else
+    = dropdown_tag(title, options: options)
diff --git a/locale/gitlab.pot b/locale/gitlab.pot
index 0cbdd2ebf67b1186fdc3ed47f020b431a89f7be0..fc2067709d77bdeb0ff0fe2deb3ec84c436a0896 100644
--- a/locale/gitlab.pot
+++ b/locale/gitlab.pot
@@ -21456,6 +21456,9 @@ msgstr ""
 msgid "Request parameter %{param} is missing."
 msgstr ""
 
+msgid "Request review from"
+msgstr ""
+
 msgid "Request to link SAML account must be authorized"
 msgstr ""
 
@@ -21726,6 +21729,9 @@ msgstr ""
 msgid "ReviewApp|Enable Review App"
 msgstr ""
 
+msgid "Reviewer"
+msgstr ""
+
 msgid "Reviewing"
 msgstr ""
 
diff --git a/spec/helpers/issuables_helper_spec.rb b/spec/helpers/issuables_helper_spec.rb
index 89a2a92ea57d74f8b61881aaeff4d25cabe4dfb0..821440db5518780955669e78e86b912af256ea0c 100644
--- a/spec/helpers/issuables_helper_spec.rb
+++ b/spec/helpers/issuables_helper_spec.rb
@@ -306,6 +306,38 @@
     end
   end
 
+  describe '#reviewer_sidebar_data' do
+    let(:user) { create(:user) }
+
+    subject { helper.reviewer_sidebar_data(user, merge_request: merge_request) }
+
+    context 'without merge_request' do
+      let(:merge_request) { nil }
+
+      it 'returns hash of reviewer data' do
+        is_expected.to eql({
+          avatar_url: user.avatar_url,
+          name: user.name,
+          username: user.username
+        })
+      end
+    end
+
+    context 'with merge_request' do
+      let(:merge_request) { build(:merge_request) }
+
+      where(can_merge: [true, false])
+
+      with_them do
+        before do
+          allow(merge_request).to receive(:can_be_merged_by?).and_return(can_merge)
+        end
+
+        it { is_expected.to include({ can_merge: can_merge })}
+      end
+    end
+  end
+
   describe '#issuable_squash_option?' do
     using RSpec::Parameterized::TableSyntax