diff --git a/components/org.wso2.carbon.identity.api.server.organization.user.invitation.management/org.wso2.carbon.identity.api.server.organization.user.invitation.management.common/src/main/java/org/wso2/carbon/identity/api/server/organization/user/invitation/management/common/UserInvitationMgtConstants.java b/components/org.wso2.carbon.identity.api.server.organization.user.invitation.management/org.wso2.carbon.identity.api.server.organization.user.invitation.management.common/src/main/java/org/wso2/carbon/identity/api/server/organization/user/invitation/management/common/UserInvitationMgtConstants.java
index 328186a641..0c390ab223 100644
--- a/components/org.wso2.carbon.identity.api.server.organization.user.invitation.management/org.wso2.carbon.identity.api.server.organization.user.invitation.management.common/src/main/java/org/wso2/carbon/identity/api/server/organization/user/invitation/management/common/UserInvitationMgtConstants.java
+++ b/components/org.wso2.carbon.identity.api.server.organization.user.invitation.management/org.wso2.carbon.identity.api.server.organization.user.invitation.management.common/src/main/java/org/wso2/carbon/identity/api/server/organization/user/invitation/management/common/UserInvitationMgtConstants.java
@@ -64,6 +64,18 @@ public enum ErrorMessage {
         ERROR_CODE_INVALID_FILTER("60009",
                 "Invalid filter.",
                 "Provided filter %s is not valid."),
+        ERROR_CODE_INVALID_APPLICATION("60009",
+                "Invalid application provided.",
+                "One of the provided applications with roles are not valid."),
+        ERROR_CODE_INVALID_CONFIRMATION_CODE_FOR_ACCEPTANCE("60010",
+                "Invalid confirmation code.",
+                "Could not accept the invitation since the confirmation code %s is not valid."),
+        ERROR_CODE_INVALID_USER("60011",
+                "Invalid user provided.",
+                "Invalid user is provided."),
+        ERROR_CODE_EXISTING_USER("60012",
+                "Authenticated user exist.",
+                "The authenticated user is already available in the organization."),
 
         // Server errors.
         ERROR_CODE_CREATE_INVITATION("65001",
@@ -78,6 +90,9 @@ public enum ErrorMessage {
         ERROR_CODE_DELETE_INVITATION("65004",
                 "Unable to delete the invitation.",
                 "Could not delete the invitation with the id %s."),
+        ERROR_CODE_ACCEPT_INVITATION("65005",
+                "Unable to accept the invitation.",
+                "Could not accept the invitation with the confirmation code %s."),
         ERROR_CODE_NOT_IMPLEMENTED("65100",
                 "Not Implemented.",
                 "Method is not implemented.");
diff --git a/components/org.wso2.carbon.identity.api.server.organization.user.invitation.management/org.wso2.carbon.identity.api.server.organization.user.invitation.management.v1/src/main/java/org/wso2/carbon/identity/api/server/organization/user/invitation/management/v1/core/GuestApiServiceCore.java b/components/org.wso2.carbon.identity.api.server.organization.user.invitation.management/org.wso2.carbon.identity.api.server.organization.user.invitation.management.v1/src/main/java/org/wso2/carbon/identity/api/server/organization/user/invitation/management/v1/core/GuestApiServiceCore.java
index 7c4ac0c1ec..8d3430f708 100644
--- a/components/org.wso2.carbon.identity.api.server.organization.user.invitation.management/org.wso2.carbon.identity.api.server.organization.user.invitation.management.v1/src/main/java/org/wso2/carbon/identity/api/server/organization/user/invitation/management/v1/core/GuestApiServiceCore.java
+++ b/components/org.wso2.carbon.identity.api.server.organization.user.invitation.management/org.wso2.carbon.identity.api.server.organization.user.invitation.management.v1/src/main/java/org/wso2/carbon/identity/api/server/organization/user/invitation/management/v1/core/GuestApiServiceCore.java
@@ -44,9 +44,12 @@
 import static org.wso2.carbon.identity.organization.user.invitation.management.constant.UserInvitationMgtConstants.ErrorMessage.ERROR_CODE_INVALID_CONFIRMATION_CODE;
 import static org.wso2.carbon.identity.organization.user.invitation.management.constant.UserInvitationMgtConstants.ErrorMessage.ERROR_CODE_INVALID_FILTER;
 import static org.wso2.carbon.identity.organization.user.invitation.management.constant.UserInvitationMgtConstants.ErrorMessage.ERROR_CODE_INVALID_INVITATION_ID;
+import static org.wso2.carbon.identity.organization.user.invitation.management.constant.UserInvitationMgtConstants.ErrorMessage.ERROR_CODE_INVALID_USER;
 import static org.wso2.carbon.identity.organization.user.invitation.management.constant.UserInvitationMgtConstants.ErrorMessage.ERROR_CODE_MULTIPLE_INVITATIONS_FOR_USER;
+import static org.wso2.carbon.identity.organization.user.invitation.management.constant.UserInvitationMgtConstants.ErrorMessage.ERROR_CODE_STORE_ROLES_APP_ID_INVALID;
 import static org.wso2.carbon.identity.organization.user.invitation.management.constant.UserInvitationMgtConstants.ErrorMessage.ERROR_CODE_UNSUPPORTED_FILTER_ATTRIBUTE;
 import static org.wso2.carbon.identity.organization.user.invitation.management.constant.UserInvitationMgtConstants.ErrorMessage.ERROR_CODE_UNSUPPORTED_FILTER_ATTRIBUTE_VALUE;
+import static org.wso2.carbon.identity.organization.user.invitation.management.constant.UserInvitationMgtConstants.ErrorMessage.ERROR_CODE_USER_ALREADY_EXISTS;
 import static org.wso2.carbon.identity.organization.user.invitation.management.constant.UserInvitationMgtConstants.ErrorMessage.ERROR_CODE_USER_NOT_FOUND;
 import static javax.ws.rs.core.Response.Status.BAD_REQUEST;
 import static javax.ws.rs.core.Response.Status.INTERNAL_SERVER_ERROR;
@@ -109,6 +112,9 @@ public InvitationSuccessResponse createInvitation(InvitationRequestBody invitati
             } else if (ERROR_CODE_ACTIVE_INVITATION_EXISTS.getCode().equals(e.getErrorCode())) {
                 throw handleException(BAD_REQUEST, UserInvitationMgtConstants.ErrorMessage
                         .ERROR_CODE_ACTIVE_INVITATION_AVAILABLE, invitation.getUsername());
+            } else if (ERROR_CODE_STORE_ROLES_APP_ID_INVALID.getCode().equals(e.getErrorCode())) {
+                throw handleException(BAD_REQUEST, UserInvitationMgtConstants.ErrorMessage
+                        .ERROR_CODE_INVALID_APPLICATION, StringUtils.EMPTY);
             }
             throw handleException(Response.Status.INTERNAL_SERVER_ERROR,
                     UserInvitationMgtConstants.ErrorMessage.ERROR_CODE_CREATE_INVITATION,
@@ -199,8 +205,24 @@ public boolean deleteInvitation(String invitationId) {
      */
     public void acceptInvitation(AcceptanceRequestBody acceptanceRequestBody) {
 
-        throw handleException(NOT_IMPLEMENTED, UserInvitationMgtConstants
-                .ErrorMessage.ERROR_CODE_NOT_IMPLEMENTED, null);
+        InvitationCoreServiceImpl invitationCoreService = new InvitationCoreServiceImpl();
+        try {
+            invitationCoreService.acceptInvitation(acceptanceRequestBody.getConfirmationCode());
+        } catch (UserInvitationMgtException e) {
+            if (ERROR_CODE_INVALID_CONFIRMATION_CODE.getCode().equals(e.getErrorCode())) {
+                throw handleException(BAD_REQUEST, UserInvitationMgtConstants.ErrorMessage
+                        .ERROR_CODE_INVALID_CONFIRMATION_CODE_FOR_ACCEPTANCE, acceptanceRequestBody
+                        .getConfirmationCode());
+            } else if (ERROR_CODE_INVALID_USER.getCode().equals(e.getErrorCode())) {
+                throw handleException(BAD_REQUEST, UserInvitationMgtConstants.ErrorMessage
+                        .ERROR_CODE_INVALID_USER, StringUtils.EMPTY);
+            } else if (ERROR_CODE_USER_ALREADY_EXISTS.getCode().equals(e.getErrorCode())) {
+                throw handleException(BAD_REQUEST, UserInvitationMgtConstants.ErrorMessage
+                        .ERROR_CODE_EXISTING_USER, StringUtils.EMPTY);
+            }
+            throw handleException(INTERNAL_SERVER_ERROR, UserInvitationMgtConstants.ErrorMessage
+                            .ERROR_CODE_ACCEPT_INVITATION, acceptanceRequestBody.getConfirmationCode());
+        }
     }
 
     private APIError handleException(Response.Status status, UserInvitationMgtConstants.ErrorMessage error,
diff --git a/pom.xml b/pom.xml
index 7fb1b9403e..e08f264b6d 100644
--- a/pom.xml
+++ b/pom.xml
@@ -717,7 +717,7 @@
         </org.wso2.carbon.identity.organization.management.core.version.range>
 
         <!-- Organization management service Version -->
-        <org.wso2.carbon.identity.organization.management.version>1.3.54
+        <org.wso2.carbon.identity.organization.management.version>1.3.61
         </org.wso2.carbon.identity.organization.management.version>
 
         <!-- Unit test versions -->