This volume contains the major part of the contributions to the 3rd Workshop on Theory and Appl ications of Abstract Data Types held in Bremen (Germany) from November 13 to November 16, 1984. The workshop, as both its predecessors (Sorpesee, 1982 and Passau, 1983), brought together many researchers interested in algebraic specifications and related topics. It provided an opportunity to present the latest, even unfinished, work and to discuss the future trends and research problems. The remarkable progress of the field re ported at the workshop provoked this volume. The present collection of papers documents the recent developments and trends in data type and software specification in theory and in practice. The theoretical con tributions pursue four objectives: the 1 iberation of the specification methods from the underlying logic (Sannella and Tarlecki; Maibaum and Sadler), the extension of the algebraic theory of data types to meet adequately the semantics of imperative programming languages and the idea of observabil ity (Wagner; Hennicker and Wirsing; Moller and Dosch; Streicher), the adaption of stepwise-refinement techniques to spec ifications with loose semantics (Beierle and Voss) and error and exception handl ing (Gogolla; Poigne). The papers oriented more towards practice are harder to classify.

Inhalt
Categorical Semantics, Or Extending Data Types to Include Memory.- Algebraic (?) Specification of Conceptual Database Schemata.- OBSCURE, A New Specification Language.- Some Thoughts on Algebraic Specification.- Implementation Specifications.- The ASSPEGIQUE Specification Environment Motivations and Design.- Towards Abstract User Interfaces for Formal System Specifications.- A Final Algebra Semantics for Errors and Exceptions.- OSI Transport Service Considered as an Abstract Data Type.- Observational Specification: A Birkhoff-Theorem.- Fair Conditional Term Rewriting Systems: Unification, Termination and Confluence.- Transformation of Interface Specifications.- Axiomatising Specification Theory.- On the Algebraic Specification of Domains.- Passing Compatibility is Almost Persistency.- Automatic Prototyping of Algebraic Specifications Using Prolog.- Error Handling for Parameterized Data Types.- Model Theory of Denotational Semantics.