A Client ID is simply a place your facility can utilize if you would like to add a client's court case number, or other identification number associated with your client to help with your own record keeping. It is not mandatory, though it can be used to search for someone. To add/change a client's ID, go to your Clients tab, and View/Edit to the right of the client you are looking for.
Type in the ID (letter and/or numbers) in the ID space provided. Always hit Save after any modification.
You can use it to help sort/search for a client. This is done in the Clients in the top Search section.