This paper covers some of the basic principles which have led to (1) discovery of liquid crystalline solutions of para-oriented aromatic polyamides, (2) direct spinning of these solutions to fibres with highly oriented extended chain configurations, and (3) realization of very high fibre tensile properties. Unusual characteristics of liquid crystalline solutions of aromatic polyamides are reviewed. Kevlar aramid fibres are based on this type of technology. Fibres have tensile strengths of 2.8 GPa and moduli ranging from 65 to 126 GPa with elongations at rupture of from 4 to 2.5% respectively. Some of the unique properties of Kevlar fibres are described.