Looks like something more people are interested in ...

There is a feature request for adding AddGroup/RemoveGroup events to Umbraco (MemberService - reimplement AddGroup / RemoveGroup Events )

In order to log membership changes, you could write your own Membership providers.

In case you only need extra logging, just inherit from the Umbraco providers (for frontend Members: MembersMembershipProvider, MembersRoleProvider) and add some logging to the methods that you are interested in.

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For example, logging for adding a member to a group (role) can be done by overriding the method AddUsersToRoles:

    public class MyRoleProvider : MembersRoleProvider
{
    public override void AddUsersToRoles(string[] usernames, string[] roleNames)
    {
        // TODO: Add your logging here ...

        // Use base implementation
        base.AddUsersToRoles(usernames, roleNames);
    }
}

In your web.config set your new providers, for example:

<roleManager enabled="true" defaultProvider="UmbracoRoleProvider">
  <providers>
    <clear />
    <add name="UmbracoRoleProvider" type="Umbraco.Extensions.MembershipProviders.MyRoleProvider" />
  </providers>
</roleManager>

Is this something that could help you audit membership changes?

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