Abstract: A free standing door jamb and trim system is completely prefabricated prior to shipping and installing the jamb in a doorway. The jamb is securely stabilized in a square orientation by gluing it to a three-sided trim frame with glued mitered square corner joints. The combination of adhesively bonding the square mitered joints of the trim frame, and adhesively bonding the trim frame to the front of the door jamb, produces an exceptionally strong door jamb assembly which can independently support a swinging door without attachment to the wall.A system and method for producing a prefabricated free sanding wooden door, jamb and trim assembly is provided. A preferred door/jamb assembly includes a first leg, a second leg and a first header. Each of the first and second legs are squarely connected to an end of the first header. A front trim frame includes a first side piece, a second side piece and a first top piece dimensioned to frame the sides and the top of the doorway.