Comparative data on the cyanovinyl and carboethoxyvinyl groups, and on the nature of the N‐substituents in a range of styryl dyes are reported, with particular respect to substituent effects on colour, dyeing properties and fastness to light and sublimation. Substitution patterns especially advantageous (and otherwise) in these dyes are concluded together with new data presented in respect of the colour of N‐β‐cyanoethyl derivatives in different solvents.