2 - 4 actively being worked on. I swap them out every few days as boredom sets in. At some point in the not too distant past, I realized that some of my UFO's ended up there only bc I was sick of working on them. I don't do small - no wall space for wall hangings, no need for more placemats/runners, etc. Most pieces are 2 - 2.5" - so a lot of pieces and many of the same unit over and over and over. Giving myself permission, if you will, to swap things out instead of working on one thing until it's done, actually makes them more likely to be finished.