I think that a guide deserves a tip based on effort put into the trip. There is a lot more work to be done on a fishless venture than there is when it's push button and quick-limits are in order. If nobody on the river is catching fish because the run is poor, then don't blame the guide if he busts his tail for you and you still come up blank. I have had the pleasure to fish with some of the best guides around, Bob Ball to follow this spring and summer . I always try to tip something, even if I come in fishless just as long as I get a full day. At least $20 per person and up to $50 if you do a CNR thing and you and your guide have to wear a belt by the end of the day to keep your pants up because you've been fishing your ass off!! You are paying for the local knowledge of the guide, if you want fish, buy 'em. It's a lot cheaper but that wouldn't be any fun now, would it?