I believe therapists try to honor confidentiality but there are little slip ups and situations that I'm surprised to hear they are allowed to discuss clients with other therapists. When I've been a little concerned with it, I've asked my t's to tell me more about the rules, or asked if there were any exceptions, or something like that, in hopes that it reinforces them against slip ups. They might think I'm a little paranoid, but I think it's worth it. I figure the threat to their reputations, let alone their jobs, if they ever get caught slipping up is a pretty significant deterrent and they are pretty careful, but I still catch minor mistakes now and then.