For some years, specification of software and hardware systems has been

influenced not only by algebraic methods but also by new developments in

logic. These new developments in logic are partly based on the use

of algorithmic techniques in deduction and proving methods, but are alsodue to new theoretical advances, to a great extent stimulated by computer
science, which have led to new types of logic and new logical calculi. The new techniques, methods and tools from logic, combined with

algebra-based ones, offer very powerful and useful tools for the

computer scientist, which may soon become practical for commercial use, where, in particular, more powerful specification tools are needed for

concurrent and distributed systems. This volume contains papers based on

lectures by leading researchers which were originally given at an

international summer school held in Marktoberdorf in 1991. The papers

aim to give a foundation for combining logic and algebra for

the purposes of specification under the aspects of automated deduction, proving techniques, concurrency and logic, abstract data types and

operational semantics, and constructive methods.