A conference on Semantics of Programming Languages and Model Theory was held at the International Conference and Research Center for Computer Science, SchloB Dägstuhl, during June 23-29, 1991. Participants from 10 countries represented a wide range of interests on the subject where the interaction of different fields is so fruitful. In particular, methods from algebra, logic and order theory were used for the solution of problems from denotational semantics and domain theory; this was reflected in some talks. Several other talks treated topics ranging from functional programming languages and database models to linear logic, boolean algebras and model theory. A number of lectures dealt with the quickly developing area of evolving algebras and in particular with evolving algebra semantics of PROLOG and its relatives. This volume contains papers presented at the conference and a few others submitted by colleagues unable to attend.