A buckle having linear engagement and disengagement activation. The buckle includes a body having a hollow sleeve portion defining a through passage extending between a proximal opening and a distal opening. Lateral openings are disposed along opposing sides of the sleeve portion. A depressible button is held in reciprocating relation within the distal opening. A male latch member having a pair of legs is adapted to be inserted into the proximal opening for locking engagement of the legs behind tabs within the sleeve portion. The latch member is releasable upon depression of the button.