Over this time period, and very much driven by the requests of these communities, Mercury has become much more than a visualizer. In the 18 years since the launch of Mercury 1.0, the fields of chemical crystallography (Watkin, 2010 ▸) and crystal engineering (Nangia & Desiraju, 2019 ▸) have changed dramatically, with much more sophisticated analysis of crystal structures now commonplace, alongside both knowledge-based and quantum chemical analysis of structures. Mercury has since become established as a prominent crystal structure visualizer with a free-to-access version available for any researcher and many thousands of citations of its first two versions. The program Mercury was first launched by the Cambridge Crystallographic Data Centre (CCDC) in 2001 as a focused crystal structure visualization tool.