Sometimes it's handy to have a little bit of extra reference information on your clients, information that is readily visible for quick reference, and even search-ready. (In full on CRMs this would be the stuff of tags or extra fields.)
CoachAccountable doesn't offer tags or extra fields, but you can get close by adding in such information to a client's "Profile Extra".
To find and set a client's Profile Extra, bring up their Client Manager (by clicking their gear icon as found in your Clients listing). There in the Basic area towards the bottom you'll find the text box that you can freely type.
Whatever you type there will be visible in you Clients listing, and can even be used for searching the listing:
A client's Profile Extra will also be visible in the profile information of their Client Page, right below their name: