At the moment, selecting two options in the same filter — say two Client Groups — returns everything that's in either one. The more boxes ticked, the longer the list gets.

The request is for the opposite: tick two groups, see only the clients that are in both.

Client Groups often get used for several things at once, so most clients sit in several groups at the same time. Narrowing a list down to the clients that meet two conditions at once isn't possible today — the filter can only widen the results, never tighten them.

The more groups a firm sets up to stay organised, the less useful the filter becomes, which feels backwards.

This is the kind of question that comes up when planning a week's work or looking for specific type of clients.

A simple "match any / match all" switch on the filter itself would do it.