TruckLover: Liquid Nails for Projects, the foam-safe kind, is suitable for attaching Atlas flextrack to foam. On my latest mini layout project I used California Home Depot white Styrofoam, because I had some lying around, and Woodland Scenics foam roadbed. I applied a bead of Liquid Nails (it comes in a big tube like caulk) where I wanted the roadbed and used a putty knife to spread it out to make a thin layer of glue that would cover the bottom of the roadbed. I gave it a while to dry, then apply another bead of glue on the WS roadbed, spread it with the putty knife, and position the track. You have to be a little careful to get it just right, and use long dressmaker's pins to hold the track down in troublesome spots, but it works just fine and it stays put. I have also heard tell of people using caulk products like DAP to secure track, as long as the stuff doesn't dissolve the styrofoam it should work.