Interlock for wall panel system

An interlock system for locking wall panel frames. Vertical frame members are provided with keyhole-shaped openings for receipt therethrough of the head of a carriage bolt in one portion and having and a second elongate slotted portion capable of a non-rotationable engagement with the carriage bolt. A threaded shaft of the carriage bolt being threadably engageable by a dowel freely rotationally held by a lever bracket whereby the dowel can be threaded along the threaded shaft to bring the lever bracket against one of the vertical frame members. The latch bracket having camming edges and being pivotal around said dowel in a past-center relation whereby to cam said camming edges against the second frame member and lock the two vertical frame members together without the use of hand tools. Access from only one side of a panel frame joint is necessary to engage or disengage the interlock system. Only one interlock is required in vertical frame members having at a separate location conventional hook and slot engageable attachments, or equivalent.