I have been having a big problem lately. Whenever I create a brush entity (func_door, func_detail, etc.), it immediately turns back into a normal brush after I deselect it (as stated in the thread title). The brush entites worked fine until about an hour ago, when they all reverted themselves to brushes for some reason. EDIT: Thanks for the help! I should have closed the map before posting for help here. Hopefully my common sense won't fail me next time!