A luminaire has a light emitting portion extending between first second end caps to define a length between the first end cap and the second end cap. The first end cap comprises a receptacle and the second end cap comprises a post both of which extend in an insertion direction. The receptacles are configured to closely receive the posts and the insertion direction is disposed transversely to the length. A method of assembling a luminaire assembly includes positioning a first end cap of a first luminaire over a second end cap of a second luminaire; moving the first end cap relative to the second end cap in the insertion direction; and inserting the post into the receptacle. An electrical connector on the first end cap may connect with a mating electrical connector on the second end cap to complete an electrical connection between the first luminaire and the second luminaire.