This volume contains the papers presented at the 3rd Glasgow Workshop on Functional Programming which was held in Ullapool, Scotland, 13-15 August 1990. Members of the functional programming groups at the universities of Glasgow and Stirling attended the workshop, together with a small number of invited participants from other universities and industry. The papers vary from the theoretical to the pragmatic, with particular emphasis on the application of theoretical ideas to practical problems. This reflects the unusually close relationship between theory and practice which characterises the functional programming research community. There is also material on the experience of using functional languages for particular applications, and on debugging and profiling functional programs.