This volume contains the papers presented at the latest Glasgow Workshop on Functional Programming, held in Portree on the Isle of Skye, 12-14 August 1991. These workshops have been held annually by the Glasgow Functional Programming group since 1988 and provide a valuable forum for members of the group and invited contributors from industry and other institutions to discuss current research work. The 29 papers contained in this volume, many of which have been rewritten since the original presentation, deal with both the theoretical and pragmatic aspects of functional programming, each paper summarizing the central issues of its subject area. A variety of themes emerged from the workshop, including relational algebra and its application to hardware design, partial evaluation and program transformation, implementation techniques and strictness analysis. Among the specific areas covered in this volume are: a new sharing mechanism for the TIM; evaluation order analysis for lazy data structures; extending deforestation for first order functional programs; a semantics for relational programming; abstractions in Ruby; and operational theories of improvement in functional languages. Functional Programming, Glasgow 1991 provides a comprehensive overview of current research in this field and should be of interest to anyone involved in the theory of functional programming or its application to practical problems.