So we ran our first "Sniff'n'Go" a couple weeks back - it's done like a trial, but it's more a "just for fun" social event run mostly by n00b dogs. Groucho did quite well... daddy not so much, as you see by his timecard:
In each case, there's a small hidden container with a Q-tip carrying the scent (birch, in this case, and paired with a bit of food for beginners like us); the dog has to find it and indicate it, and the handler has to read the dog's indication and call "Alert". If he's right, it stops the clock - clock starts either when the handler gives the command to start, or when the dog's nose crosses the threshold to the search area, whichever comes first.
Points are allotted by the judges based on various things like how the handler works the leash, reads the dog, stays out of the way... points can be deducted for things like dropping food in the search area (will create a distraction for later dogs). I think everyone got 25 points this time
"Container" search involves two rows of identical closed cardboard boxes (20 or so), with the "hide" in one.
"Exterior" search takes place around outside objects - in this case, some picnic chairs, a picnic table, and a couple farm implements.
"Interior" search was in part of a room and has the hide in amongst regular indoor objects (this one was extra tricky - UNDER a garbage can!)
"Vehicle" search has the hide somewhere on the exterior of a vehicle, the tricky part being there are multiple vehicles in the search area.
Oh yes, and the "P" in the comments means "Pronounced" and it's the judge's indication that they think the dog and handler performed exceptionally well together!