The snap-in trigger for mounting in a trigger sprayer housing comprises a trigger which includes flexible members carrying pivotal mounting elements which mate with corresponding elements in a base, e.g., the sprayer housing. The flexible members are flexed towards each other during attachment of the trigger to the base, to allow easy mating of the pivotal mounting elements. The trigger also includes a flexible locking member which can be pivoted between a first position in which the locking members is spaced apart from the vicinity of the pivotal mounting elements, (e.g., during mating of the pivotal members while the flexible members are flexed together) and a second position in which the locking member is positioned directly between the flexible members in the vicinity of the pivotal mounting elements, preventing the flexible members from moving towards one another, and thus assuring proper mating configuration between the pivotal mounting members. The locking member also includes secondary locking means f