# Atlassian Crowd Support

Only available in Sonatype Nexus RepositoryTM Pro. Interested in a free trial? [Start here](/content/products/repository-pro/trial/index.html).

Atlassian Crowd is a single sign-on and identity management product that many organizations use to consolidate user accounts and control which users and groups have access to which applications. Atlassian Crowd support is a feature preinstalled and ready to configure in Nexus Repository Manager Pro. Nexus Repository Manager contains a security realm that allows you to configure the repository manager to authenticate against an Atlassian Crowd instance.

**Warning**

Using LDAP and Crowd Realms together in the repository manager may work, but this is not supported. If you already use LDAP support, we recommend adding your LDAP server as a Crowd directory accessible to the Crowd application instead of using both LDAP and Crowd realms in the repository manager.