King moves must be normal, legal chess King moves. Captures must be normal, legal chess captures. Pawn promotions must be normal, legal chess Pawn promotions. A Pawn may not be placed on the first rank or the eighth rank, except during a normal promotion. Of course, checks must be respected.
Rules regarding check and mate are the same as in chess.
Bill Smythe sent the information on Half Bughouse. Edited by Hans Bodlaender.