From 1950 Jean Muir worked as a seller and fashion sketcher for Liberty's in London and was then employed as a designer by Jaeger. In 1961 she established the firm 'Jane and Jane'. A dress she made from Liberty print silk for this label won the Bath Costume Museum 'Dress of the Year' Award for 1964. In 1966 Muir started her own business with her husband, selling clothes to selected shops worldwide.
Muir's outfits were known for their long, fluid lines and skilful tailoring. Favourite fabrics included jersey, crepe and suede, usually in dark, plain colours. Muir's style is classic rather than fashionable.