I've usually swept in larger group rides because A) I'm very conspicuous with Clearwater Darlas, so the lead rider can see me. If he sees me, everything's good. B) I carry tools & extra gas in MSR bottles as well as a SpotX GPS for comms and a medium-sized first aid kit. C) I've had sufficient first aid training and experience to handle most situations. DAMHIKT. If I lead, it's only one or two other riders and I ALWAYS keep an eye on the guy behind me, and if possible, on the sweep. I've had one guy go tearing off down an unknown road and I spent a while checking every embankment to make sure he hadn't crashed. He finally came back to see where I was and I struggled not to curse him out. He got the message. I try to get contact info of the lead & sweep, depending, so I can, should circumstances warrant (hospital, etc.) be able to contact them. Being in a hospital with a concussed friend and not having their contact info is difficult. If there's a rest stop, the leaders better damn well give the tail guys time to rest before heading out again. One guy got a beesting and we stopped to take care of it. (NOTE: carry beesting ointment!!) The stop sucked up almost ten minutes and when we got to where the rest of the group was, they were ready to leave immediately. Nope. Give us some time to chill, peeps. Be nice or we won't ride with you again.