The evolution of the Collaborative Computational Project No. 4 (CCP4) has been described in a new article by Agirre et al. [(2023). Acta Cryst. D79, 449-461] that should provide the definitive reference for the CCP4 suite of programs.
Keywords: CCP4; Collaborative Computational Project No. 4; X-ray crystallography software; macromolecular crystallography.
open access.