Uniform thin films are needed for the exploration and exploitation of the fascinating optical and electronic properties of the phthalocyanine (Pc) macrocycle. Spin-coating has been demonstrated to be a simple, fast and reproducible method of fabricating uniform films. However, solubility in a volatile organic solvent is a prerequisite for this technique and previous studies have shown that groups placed on the Pc macrocycle can have a profound effect on the nanoscale structure of the resulting film. In this paper we attempt to establish some fundamental structure–property relationships which determine the molecular packing within such films. Previous studies are reviewed and the film forming properties of a number of Pc derivatives are examined. In particular, the formation of films in which the Pc cores are isolated from each other by the use of novel, sterically crowded hexadeca-substituted Pcs is examined.