An improved housing (15, 17) and associated latching mechanism that render practicable the implementation of a completely modular computer system. The latching mechanism effects simple positive engagement and disengagement of the pin and socket connectors (22, 20) as respective outer surfaces of a first wall (25) on a first module housing (15) and a second wall (27) on a second module housing (17) are brought together or separated. The second wall (27) carries a plurality of hooking members (30) which pass through corresponding apertures (32) in the first wall (25) and are captured and restrained by a reciprocable latch bar (50) inside the first housing (15). A rotary latch (37) engages the latch bar (50) such that actuation of a handle (40) on the rotary latch (37) causes reciprocation of the latch bar (50) between a first accommodating position and a second capturing position. The hooking members (30) have respective camming surfaces (48) in spaced facing relationship to the external surface of the second wall (27) while the latch bar (50) is formed with complementarily configured camming surfaces (53) spaced and located so as to engage the camming surfaces (48) on the hooking members (30) when the latch bar (50) moves towards its capturing position. The hooking members (30) are distributed over the surface so that the modules (10, 12) are drawn together in a direction that minimizes sideways forces on the pins in the connector (22).