To place a window in a wall is to strike a deal with the world beyond it: I can look out at you and you can look through it to me. The love struck teen on curfew can climb out in the middle of the night-and the cat burglar can climb in. A window of opportunity is also a window of vulnerability. Most of all, though, a window is a frame-or a lens-that's as important for what it conceals as for what it reveals. And for the artists in this virtual exhibit, hosted in conjunction with ApartmentTherapy.com, the opposite could be said to be true, too: A lens is a window. Stand in front of a window and what exists on the other side becomes a composition. A small segment of the world comes into focus for a moment-this is your view. These photographers travel with their windows, and this is their view.