diff --git a/README.md b/README.md
index f875f8e90..5508df15e 100644
--- a/README.md
+++ b/README.md
@@ -185,9 +185,9 @@ so can use it to determine whether a user is new to you.  For example:
 ActivityDetails activityDetails;
 try {
     activityDetails = client.getActivityDetails(token);
-    Optional<YourAppUserClass> user = yourUserSearchMethod(activityDetails.getUserId());
+    Optional<YourAppUserClass> user = yourUserSearchMethod(activityDetails.getRememberMeId());
     if (user.isPresent()) {
-        String userId = activityDetails.getUserId();
+        String rememberMeId = activityDetails.getRememberMeId();
         String base64Selfie = activityDetails.getBase64Selfie();
         Attribute<Image> selfie = profile.getSelfie();
         Image selfieValue = selfie.getValue();
@@ -210,7 +210,7 @@ try {
 }
 ```
 
-Where `yourUserSearchMethod` is a method in your app that finds the user for the given userId.
+Where `yourUserSearchMethod` is a method in your app that finds the user for the given rememberMeId.
 Regardless of whether the user is new to your app, Yoti will always provide the profile.  So you don't necessarily need to store it.
 
 ### Attributes
diff --git a/yoti-sdk-api/src/main/java/com/yoti/api/client/ActivityDetails.java b/yoti-sdk-api/src/main/java/com/yoti/api/client/ActivityDetails.java
index 076daf3b2..c00abb7d8 100644
--- a/yoti-sdk-api/src/main/java/com/yoti/api/client/ActivityDetails.java
+++ b/yoti-sdk-api/src/main/java/com/yoti/api/client/ActivityDetails.java
@@ -23,13 +23,22 @@ public interface ActivityDetails {
     ApplicationProfile getApplicationProfile();
 
     /**
-     * Return the user ID, which is a unique, stable identifier for a user in the context of an application/user
+     * Deprecated.  Please use getRememberMeId() instead.
+     *
+     * @return user ID.
+     */
+    @Deprecated
+    String getUserId();
+
+    /**
+     * Return the remember-me ID, which is a unique, stable identifier for a user in the context of an application/user
      * interaction. You can be use it to identify returning users. Note that it is different for the same user in
      * different applications.
      *
      * @return user ID.
      */
-    String getUserId();
+    String getRememberMeId();
+
 
     /**
      * Time and date of the activity.
diff --git a/yoti-sdk-impl/src/main/java/com/yoti/api/client/spi/remote/SimpleActivityDetails.java b/yoti-sdk-impl/src/main/java/com/yoti/api/client/spi/remote/SimpleActivityDetails.java
index bc5bd1599..653076e6e 100644
--- a/yoti-sdk-impl/src/main/java/com/yoti/api/client/spi/remote/SimpleActivityDetails.java
+++ b/yoti-sdk-impl/src/main/java/com/yoti/api/client/spi/remote/SimpleActivityDetails.java
@@ -11,15 +11,15 @@
 
 final class SimpleActivityDetails implements ActivityDetails {
 
-    private final String userId;
+    private final String rememberMeId;
     private final ApplicationProfile applicationProfile;
     private final HumanProfile userProfile;
     private final Date timestamp;
     private final String receiptId;
     private final String base64Selfie;
 
-    public SimpleActivityDetails(String userId, Profile userProfile, Profile applicationProfile, Date timestamp, byte[] receiptId) {
-        this.userId = notNull(userId, "User id");
+    public SimpleActivityDetails(String rememberMeId, Profile userProfile, Profile applicationProfile, Date timestamp, byte[] receiptId) {
+        this.rememberMeId = notNull(rememberMeId, "Remember Me id");
         this.userProfile = HumanProfileAdapter.wrap(notNull(userProfile, "User profile"));
         this.applicationProfile = ApplicationProfileAdapter.wrap(notNull(applicationProfile, "Application profile"));
         this.timestamp = notNull(timestamp, "Timestamp");
@@ -43,8 +43,14 @@ public ApplicationProfile getApplicationProfile() {
     }
 
     @Override
+    @Deprecated
     public String getUserId() {
-        return userId;
+        return getRememberMeId();
+    }
+
+    @Override
+    public String getRememberMeId() {
+        return rememberMeId;
     }
 
     @Override
diff --git a/yoti-sdk-impl/src/test/java/com/yoti/api/client/spi/remote/ActivityDetailsFactoryTest.java b/yoti-sdk-impl/src/test/java/com/yoti/api/client/spi/remote/ActivityDetailsFactoryTest.java
index 5337cbd3a..64b8a419e 100644
--- a/yoti-sdk-impl/src/test/java/com/yoti/api/client/spi/remote/ActivityDetailsFactoryTest.java
+++ b/yoti-sdk-impl/src/test/java/com/yoti/api/client/spi/remote/ActivityDetailsFactoryTest.java
@@ -5,6 +5,7 @@
 import static com.yoti.api.client.spi.remote.util.CryptoUtil.generateSymmetricKey;
 
 import static org.bouncycastle.util.encoders.Base64.decode;
+import static org.bouncycastle.util.encoders.Base64.toBase64String;
 import static org.hamcrest.core.StringContains.containsString;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertSame;
@@ -52,8 +53,8 @@ public class ActivityDetailsFactoryTest {
     private static final DateFormat RFC3339_FORMAT = new SimpleDateFormat(RFC3339_PATTERN);
     private static final String VALID_TIMESTAMP = RFC3339_FORMAT.format(DATE);
 
-    private static final String SOME_USER_ID_STRING = "aBase64EncodedUserId";
-    private static final byte[] SOME_USER_ID_BYTES = decode(SOME_USER_ID_STRING);
+    private static final String SOME_REMEMBER_ME_ID_STRING = toBase64String("aBase64EncodedRememberMeId".getBytes());
+    private static final byte[] SOME_REMEMBER_ME_ID_BYTES = decode(SOME_REMEMBER_ME_ID_STRING);
     private static final String ENCODED_RECEIPT_STRING = "base64EncodedReceipt";
     private static final byte[] DECODED_RECEIPT_BYTES = decode(ENCODED_RECEIPT_STRING);
 
@@ -128,7 +129,7 @@ public void shouldGetCorrectProfilesFromProfileReader() throws Exception {
         Receipt receipt = new Receipt.Builder()
                 .withWrappedReceiptKey(validReceiptKey)
                 .withTimestamp(VALID_TIMESTAMP)
-                .withRememberMeId(SOME_USER_ID_BYTES)
+                .withRememberMeId(SOME_REMEMBER_ME_ID_BYTES)
                 .withProfile(PROFILE_CONTENT)
                 .withOtherPartyProfile(OTHER_PROFILE_CONTENT)
                 .withReceiptId(DECODED_RECEIPT_BYTES)
@@ -140,7 +141,8 @@ public void shouldGetCorrectProfilesFromProfileReader() throws Exception {
 
         assertSame(otherProfileMock, getWrappedProfile(result.getUserProfile()));
         assertSame(profileMock, getWrappedProfile(result.getApplicationProfile()));
-        assertEquals(SOME_USER_ID_STRING, result.getUserId());
+        assertEquals(SOME_REMEMBER_ME_ID_STRING, result.getRememberMeId());
+        assertEquals(SOME_REMEMBER_ME_ID_STRING, result.getUserId());
         assertEquals(ENCODED_RECEIPT_STRING, result.getReceiptId());
         assertEquals(DATE, result.getTimestamp());
     }
diff --git a/yoti-sdk-impl/src/test/java/com/yoti/api/client/spi/remote/SimpleActivityDetailsTest.java b/yoti-sdk-impl/src/test/java/com/yoti/api/client/spi/remote/SimpleActivityDetailsTest.java
index c0e64a5c3..416ba82e0 100644
--- a/yoti-sdk-impl/src/test/java/com/yoti/api/client/spi/remote/SimpleActivityDetailsTest.java
+++ b/yoti-sdk-impl/src/test/java/com/yoti/api/client/spi/remote/SimpleActivityDetailsTest.java
@@ -14,7 +14,7 @@
 
 public class SimpleActivityDetailsTest {
 
-    private static final String USER_ID = "YmFkYWRhZGEtZGFkYWJhZGEK";
+    private static final String REMEMBER_ME_ID = "YmFkYWRhZGEtZGFkYWJhZGEK";
     private static final Profile USER_PROFILE = Mockito.mock(Profile.class);
     private static final Profile APP_PROFILE = Mockito.mock(Profile.class);
     private static final Profile USER_PROFILE_WRAPPER = HumanProfileAdapter.wrap(USER_PROFILE);
@@ -31,50 +31,51 @@ public void shouldFailConstructionForNullRememberMeId() {
 
     @Test(expected = IllegalArgumentException.class)
     public void shouldFailConstructionForNullUserProfile() {
-        new SimpleActivityDetails(USER_ID, null, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
+        new SimpleActivityDetails(REMEMBER_ME_ID, null, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
     }
 
     @Test(expected = IllegalArgumentException.class)
     public void shouldFailConstructionForNullAppProfile() {
-        new SimpleActivityDetails(USER_ID, USER_PROFILE, null, TIMESTAMP, RECEIPT_ID);
+        new SimpleActivityDetails(REMEMBER_ME_ID, USER_PROFILE, null, TIMESTAMP, RECEIPT_ID);
     }
 
     @Test(expected = IllegalArgumentException.class)
     public void shouldFailConstructionForNullTimestamp() {
-        new SimpleActivityDetails(USER_ID, USER_PROFILE, APP_PROFILE, null, RECEIPT_ID);
+        new SimpleActivityDetails(REMEMBER_ME_ID, USER_PROFILE, APP_PROFILE, null, RECEIPT_ID);
     }
 
     @Test(expected = IllegalArgumentException.class)
     public void shouldFailConstructionForNullReceiptId() {
-        new SimpleActivityDetails(USER_ID, USER_PROFILE, APP_PROFILE, TIMESTAMP, null);
+        new SimpleActivityDetails(REMEMBER_ME_ID, USER_PROFILE, APP_PROFILE, TIMESTAMP, null);
     }
 
     @Test(expected = IllegalArgumentException.class)
     public void shouldFailConstructionForNullProfile() {
-        new SimpleActivityDetails(USER_ID, null, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
+        new SimpleActivityDetails(REMEMBER_ME_ID, null, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
     }
 
     @Test
     public void shouldReturnUserId() {
-        SimpleActivityDetails s = new SimpleActivityDetails(USER_ID, USER_PROFILE, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
-        assertEquals(USER_ID, s.getUserId());
+        SimpleActivityDetails s = new SimpleActivityDetails(REMEMBER_ME_ID, USER_PROFILE, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
+        assertEquals(REMEMBER_ME_ID, s.getRememberMeId());
+        assertEquals(REMEMBER_ME_ID, s.getUserId());
     }
 
     @Test
     public void shouldReturnUserProfile() {
-        SimpleActivityDetails s = new SimpleActivityDetails(USER_ID, USER_PROFILE, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
+        SimpleActivityDetails s = new SimpleActivityDetails(REMEMBER_ME_ID, USER_PROFILE, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
         assertEquals(USER_PROFILE_WRAPPER, s.getUserProfile());
     }
 
     @Test
     public void shouldReturnAppProfile() {
-        SimpleActivityDetails s = new SimpleActivityDetails(USER_ID, APP_PROFILE, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
+        SimpleActivityDetails s = new SimpleActivityDetails(REMEMBER_ME_ID, APP_PROFILE, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
         assertEquals(APP_PROFILE_WRAPPER, s.getApplicationProfile());
     }
 
     @Test
     public void shouldReturnReceiptId() {
-        SimpleActivityDetails s = new SimpleActivityDetails(USER_ID, USER_PROFILE, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
+        SimpleActivityDetails s = new SimpleActivityDetails(REMEMBER_ME_ID, USER_PROFILE, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
         assertEquals(RECEIPT_ID_STRING, s.getReceiptId());
     }
 
@@ -83,7 +84,7 @@ public void shouldReturnBase64SelfieIfSelfieSet() {
         Attribute selfie = new SimpleAttribute("selfie", new JpegAttributeValue(SOME_SELFIE_BYTES));
         SimpleProfile profile = new SimpleProfile(Collections.<Attribute<?>>singletonList(selfie));
 
-        SimpleActivityDetails result = new SimpleActivityDetails(USER_ID, profile, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
+        SimpleActivityDetails result = new SimpleActivityDetails(REMEMBER_ME_ID, profile, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
 
         String expected = "data:image/jpeg;base64," + Base64.toBase64String(SOME_SELFIE_BYTES);
         assertEquals(expected, result.getBase64Selfie());
@@ -94,7 +95,7 @@ public void shouldReturnBlankBase64SelfieIfSelfieNotSet() {
         Attribute familyName = new SimpleAttribute("family_name", "Smith");
         SimpleProfile profile = new SimpleProfile(Collections.<Attribute<?>>singletonList(familyName));
 
-        SimpleActivityDetails result = new SimpleActivityDetails(USER_ID, profile, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
+        SimpleActivityDetails result = new SimpleActivityDetails(REMEMBER_ME_ID, profile, APP_PROFILE, TIMESTAMP, RECEIPT_ID);
 
         assertEquals("", result.getBase64Selfie());
     }
diff --git a/yoti-sdk-spring-boot-example/src/main/java/com/yoti/api/examples/springboot/YotiLoginController.java b/yoti-sdk-spring-boot-example/src/main/java/com/yoti/api/examples/springboot/YotiLoginController.java
index 2c238dd8d..ba1a7e7a9 100644
--- a/yoti-sdk-spring-boot-example/src/main/java/com/yoti/api/examples/springboot/YotiLoginController.java
+++ b/yoti-sdk-spring-boot-example/src/main/java/com/yoti/api/examples/springboot/YotiLoginController.java
@@ -65,7 +65,7 @@ public String doLogin(@RequestParam("token") final String token, final Model mod
         }
 
         // load activityDetails into ui model
-        model.addAttribute("userId", activityDetails.getUserId());
+        model.addAttribute("rememberMeId", activityDetails.getRememberMeId());
         model.addAttribute("base64Selfie", activityDetails.getBase64Selfie());
 
         // load humanProfile data into ui model
diff --git a/yoti-sdk-spring-boot-example/src/main/resources/templates/index.html b/yoti-sdk-spring-boot-example/src/main/resources/templates/index.html
index 9ffde3cd1..3aafd40ac 100644
--- a/yoti-sdk-spring-boot-example/src/main/resources/templates/index.html
+++ b/yoti-sdk-spring-boot-example/src/main/resources/templates/index.html
@@ -8,7 +8,7 @@
         <script src="https://sdk.yoti.com/clients/browser.2.1.0.js"></script>
     </head>
     <body>
-    <p th:text="${userId}"/>
+    <p th:text="${rememberMeId}"/>
     <!-- This span will create the Yoti button -->
     <span data-th-attr="data-yoti-application-id=${applicationId}">
         Use Yoti
diff --git a/yoti-sdk-spring-boot-example/src/main/resources/templates/profile.html b/yoti-sdk-spring-boot-example/src/main/resources/templates/profile.html
index 73080e530..51909e2bc 100644
--- a/yoti-sdk-spring-boot-example/src/main/resources/templates/profile.html
+++ b/yoti-sdk-spring-boot-example/src/main/resources/templates/profile.html
@@ -14,7 +14,7 @@
                 <th>Verifiers</th>
             <tr>
                 <td>User ID:</td>
-                <td><p th:text="${userId}"/></td>
+                <td><p th:text="${rememberMeId}"/></td>
             </tr>
             <tr>
                 <td>Selfie:</td>