A modular sprinkler or sprayhead assembly includes a sprinkler body including an inlet portion adapted for connection to a feed conduit, and an outlet portion for emitting water to atmosphere. A cap is removably attached to the sprinkler body, the cap mounting a distributor assembly (fixed or rotatable) adapted to receive and distribute water emitted from the outlet portion. The cap has a flexible and radially extending latching element releasably engaged within a detent provided on the sprinkler body for releasably holding the cap on the sprinkler body. The distributor assembly may include a brake housing provided with an annular groove, and the cap may then be provided with a hinged projection for releasable engagement with the annular groove. By this construction, the cap and associated distributor comprise a separable unit which is easily assembled and disassembled from the sprinkler body. In turn, the distributor/brake unit is easily assembled and disassembled from the cap.