This book contains the eight invited papers presented at the workshop on Formal Aspects of Measurement held at South Bank University on 5th May 1991, organised by the British Computer Society's Special Interest Group on Formal Aspects of Computer Science (FACS). In addition, there are five papers which have been included because of their relevance to the subject of the workshop. The book represents something of a landmark in software engineering research. The British Computer Society's Special Interest Group on Formal Aspects of Computer Science (FACS) has an established reputation among researchers in formal methods of software specification, design and validation. These researchers have not in the past paid much attention to software measurement. Perhaps software measurement research was felt to have emphasised its management potential at the expense of proper scientific foundations? At any rate, for the FACS group to host a workshop in this field is recognition of the significant body of formal measurement theories and techniques which has now become available to software engineers.