The basement membrane is a specialized sheet-like extracellular matrix (ECM) that surrounds most tissues. The mechanisms underlying adhesion between basement membranes, which is important for neighbouring tissue alignment, are unclear. Studying Caenorhabditis elegans uterine–vulval attachments, Morrissey et al. found that the ECM component hemicentin, and VAB-10A (plakin) and INA-1/PAT-3 (integrin), connect adjacent basement membranes. Genetic analyses, transmission electron microscopy, tissue shifting experiments and live-cell imaging revealed that hemicentin is secreted into the basement membrane by the anchor cell (a specialized uterine cell) prior to its invasion into the vulva, and forms punctae; these link the juxtaposed gonadal and ventral basement membranes to allow anchor cells to invade through them and establish uterine–vulval connections. INA-1/PAT-3 and VAB-10A were required to establish and stabilize hemicentin-containing adhesions, respectively.