diff --git a/app/extensions/brave/locales/en-US/preferences.properties b/app/extensions/brave/locales/en-US/preferences.properties
index 460256c424c..7368ebf6316 100644
--- a/app/extensions/brave/locales/en-US/preferences.properties
+++ b/app/extensions/brave/locales/en-US/preferences.properties
@@ -249,6 +249,8 @@ enablePinterest=Enable Pinterest
 enableMetamask=Enable MetaMask
 useHardwareAcceleration=Use hardware acceleration when available *
 useSmoothScroll=Enable smooth scrolling *
+siteIsolation=Strict Site Isolation
+useSiteIsolation=Enhance security by loading each site in its own process (experimental) *
 defaultZoomLevel=Default zoom level
 toolbarUserInterfaceScale=Toolbar and UI elements scale
 en-US=English (U.S.)
@@ -360,7 +362,6 @@ scaleSizeNormal=Normal
 scaleSizeLarger=Larger
 scaleSizeSuper=Supersize
 urlBarOptions=URL Bar Options
-disableTitleMode=Always show the URL bar
 wideURLbar=Use wide URL bar
 autoplay=Autoplay Media
 tabPreviewTiming=Time to wait before previewing a tab
diff --git a/app/index.js b/app/index.js
index bada8654569..9f81dcec67a 100644
--- a/app/index.js
+++ b/app/index.js
@@ -99,17 +99,22 @@ let loadAppStatePromise = SessionStore.loadAppState()
 
 // Some settings must be set right away on startup, those settings should be handled here.
 loadAppStatePromise.then((initialImmutableState) => {
-  const {HARDWARE_ACCELERATION_ENABLED, SMOOTH_SCROLL_ENABLED, SEND_CRASH_REPORTS} = require('../js/constants/settings')
-  CrashHerald.init(getSetting(SEND_CRASH_REPORTS, initialImmutableState.get('settings')))
+  const {HARDWARE_ACCELERATION_ENABLED, SMOOTH_SCROLL_ENABLED, SEND_CRASH_REPORTS, SITE_ISOLATION_ENABLED} = require('../js/constants/settings')
+  const initialSettings = initialImmutableState.get('settings')
+  CrashHerald.init(getSetting(SEND_CRASH_REPORTS, initialSettings))
 
   telemetry.setCheckpointAndReport('state-loaded')
-  if (getSetting(HARDWARE_ACCELERATION_ENABLED, initialImmutableState.get('settings')) === false) {
+  if (getSetting(HARDWARE_ACCELERATION_ENABLED, initialSettings) === false) {
     app.disableHardwareAcceleration()
   }
 
-  if (getSetting(SMOOTH_SCROLL_ENABLED, initialImmutableState.get('settings')) === false) {
+  if (getSetting(SMOOTH_SCROLL_ENABLED, initialSettings) === false) {
     app.commandLine.appendSwitch('disable-smooth-scrolling')
   }
+
+  if (getSetting(SITE_ISOLATION_ENABLED, initialSettings) === true) {
+    app.commandLine.appendSwitch('site-per-process')
+  }
 })
 
 const notifyCertError = (webContents, url, error, cert) => {
diff --git a/docs/state.md b/docs/state.md
index 0ec7fef7fc3..fe2178b10a3 100644
--- a/docs/state.md
+++ b/docs/state.md
@@ -428,6 +428,7 @@ AppStore
     'search.default-search-engine': string, // name of search engine, from js/data/searchProviders.js
     'search.offer-search-suggestions': boolean, // true if suggestions should be offered from the default search engine when available.
     'security.flash.installed': boolean,
+    'security.site-isolation-enabled': boolean,
     'shields.blocked-count-badge': boolean, // true if blocked counts on the shield button should be enabled
     'shields.compact-bravery-panel': boolean, // true if the compact Bravery panel should be enabled
     'security.passwords.active-password-manager': string, // name of active password manager
diff --git a/js/about/preferences.js b/js/about/preferences.js
index 49e72491b0a..b4e67d738b9 100644
--- a/js/about/preferences.js
+++ b/js/about/preferences.js
@@ -701,6 +701,10 @@ class SecurityTab extends ImmutableComponent {
       <SettingsList>
         <SettingCheckbox dataL10nId='doNotTrack' prefKey={settings.DO_NOT_TRACK} settings={this.props.settings} onChangeSetting={this.props.onChangeSetting} />
       </SettingsList>
+      <DefaultSectionTitle data-l10n-id='siteIsolation' />
+      <SettingsList>
+        <SettingCheckbox dataL10nId='useSiteIsolation' prefKey={settings.SITE_ISOLATION_ENABLED} settings={this.props.settings} onChangeSetting={this.props.onChangeSetting} />
+      </SettingsList>
       <SitePermissionsPage siteSettings={this.props.siteSettings} names={permissionNames} />
       <div data-l10n-id='requiresRestart' className={css(commonStyles.requiresRestart)} />
     </div>
@@ -876,6 +880,7 @@ class AboutPreferences extends React.Component {
       settings.PDFJS_ENABLED,
       settings.TORRENT_VIEWER_ENABLED,
       settings.SMOOTH_SCROLL_ENABLED,
+      settings.SITE_ISOLATION_ENABLED,
       settings.SEND_CRASH_REPORTS,
       settings.SPELLCHECK_ENABLED,
       settings.SPELLCHECK_LANGUAGES
diff --git a/js/constants/appConfig.js b/js/constants/appConfig.js
index 09be6358682..f96a4d36f69 100644
--- a/js/constants/appConfig.js
+++ b/js/constants/appConfig.js
@@ -158,6 +158,7 @@ module.exports = {
     'security.fullscreen.content': fullscreenOption.ALWAYS_ASK,
     'security.autoplay.media': autoplayOption.ALWAYS_ALLOW,
     'security.flash.installed': false,
+    'security.site-isolation-enabled': false,
     'shields.blocked-count-badge': true,
     'shields.compact-bravery-panel': false,
     // sync
diff --git a/js/constants/settings.js b/js/constants/settings.js
index 9d5aa292a2b..51e42a61d81 100644
--- a/js/constants/settings.js
+++ b/js/constants/settings.js
@@ -51,6 +51,7 @@ const settings = {
   FLASH_INSTALLED: 'security.flash.installed',
   FULLSCREEN_CONTENT: 'security.fullscreen.content',
   AUTOPLAY_MEDIA: 'security.autoplay.media',
+  SITE_ISOLATION_ENABLED: 'security.site-isolation-enabled',
   // Autofill
   AUTOFILL_ENABLED: 'privacy.autofill-enabled',
   // Payments Tab