Thomas Südhof discusses the cell-biological principles underlying the assembly of specific synaptic connections with defined properties that control neural circuits.

In this issue, Bowman et al. describe an unprecedented mechanism where two sorting complexes, AP-3 and BLOC-1, the latter bound to syntaxin 13, work as a fail-safe to recognize sorting signals in VAMP7, a membrane protein required for fusion to melanosomes. Their observations define one of the first examples of distributed robustness in membrane traffic mechanisms.

Phuyal and Farhan discuss works from Shomron et al. and Weigel et al. that provide exciting new insight to the debate about the nature of ER-to-Golgi carriers.