Even though I don't look at the clock, I notice when my T sneaks a glance at it...even though i mostly stare at the floor. When the glances become more frequent, i know it means the session is ending. She does wind it down though and usually concludes with something that makes it so i can get off her couch. At my last session she must have seen how tired i was (therapy is so exhausting!), and went "If you didn't have to feed your cat, I'd let you sleep here," which made me laugh, and then get off her couch.