Abstract: A reinforced assembly for a door opening includes an elongated reinforcement strip having an L-shaped transverse cross-section of one short leg and one long leg, the long leg for mounting on a door jamb face and the short leg for mounting on a door jamb edge. The short leg has a transverse extent such that upon the reinforcement strip being mounted on a door opening, the transverse extent of the short leg of the reinforcement strip is no greater than the offset distance between the forward edge of the adjacent door casing panel and the door jamb face to which the long leg is mounted. For securing the strip to the door jamb and for receiving the latch of a door, a plurality of spaced openings are formed in the long leg of the reinforcement strip, at least one of the openings being generally rectangular to receive the tongue of a door latch mechanism. The elongated reinforcement strip is adapted to be mounted on a door opening free of modifications to the door jamb, door casing panel and door opening.