Using linear elastic dislocation dynamics simulations, we show that junction formation between dislocations from various interacting slip systems can be predicted by a simple self-energy calculation. We find that this prediction is robust: dislocation curvature and external stress produce little change in the simulation results for junction formation. One key to this success appears to be a separation of timescales, where movement of the far away dislocation arms (under, for example, external stress) is typically slow compared to the process of making a junction. The self-energy calculation we describe gives a rule for dislocation encounters which should allow a considerable saving in computational effort, allowing one to impose correct interaction outcomes without calculating the interactions in detail. We also find that dislocations often come together under attraction without forming a junction. The resulting “cross-linked” state provides an additional type of connection between dislocations. We include preliminary results on the persistence of junctions and cross-linked states under stress.