A key for assembling at least a portion of a stay-in-place form-work for casting a structure from concrete or other curable construction materials. The stay-in-place form-work comprises a first elongate panel comprising a first edge component and a second elongate panel comprising a second edge component. The first and second panels are connectable in an edge-to-edge relationship wherein the first and second edge components engage one another. The key comprises a plurality of connector components for slidable engagement with complementary panel connector components on at least one of the first and second panels and a locking component for forcing the first and second edge components into a locked configuration as the key is moved longitudinally relative to the first and second panels while slidably engaged thereto.