How to set a limit to the maximum number of users/employees ?

Hi Forum,

SugarCRM 6.5.20

I would like to set a limit to the number of users/employees that can be created in a given distribution.

Is there a way that this can be achieved ?

eg. If I set the limit to 50, when the administrator attempts to create the 51st user, it should not work.

Thank you,

BP