Experimentally observed configurations of the integration of glide dislocations into a Σ = 9 boundary are explained in analogy to cross-slip in the bulk. Crystallographically possible dissociations of the bulk dislocations into complete or imperfect dislocations of the DSC lattice are discussed. The energetically most favorable configurations serve as activated intermediary steps in thermal activation involving both glide and climb. Thermal activation blocks 60° dislocations at the boundary, but helps screw dislocations to traverse it.