ECOOP '91 is the fifth annual European Conference on Object-Oriented Programming. From their beginning, the ECOOP conferences have been very successful as a forum of high scientific quality where the newest devel- opments connected to object-oriented programming and related areas could be presented and discussed. Over the last few years object-oriented technology has gained widespread use and considerable popularity. In parallel with this, the field has matured scientifically, but there is still a lot of room for new ideas and for hot debates over fundamental issues, as these proceedings show. The 22 papers in this volume were selected by the programme committee from 129 submissions. Important issues discussed in the contributions are language design, specification, databases, concurrency types and software development.

This volume constitutes the proceedings of the sixth European Conference on Object-Oriented Programming (ECOOP), held in Utrecht, The Netherlands, June 29 - July 3, 1992. Since the "French initiative" to organize the first conference in Paris, ECOOP has been a very successful forum for discussing the state of the art of object orientation. ECOOP has been able to attract papers of a high scientific quality as well as high quality experience papers describing the pros and cons of using object orientation in practice. This duality between theory and practice within object orientation makes a good example of experimental computer science. The volume contains 24 papers, including two invited papers and 22 papers selected by the programme committee from 124 submissions. Each submitted paper was reviewed by 3-4 people, and the selection of papers was based only on the quality of the papers themselves.

ECOOP '91 is the fifth annual European Conference on Object-Oriented Programming. From their beginning, the ECOOP conferences have been very successful as a forum of high scientific quality where the newest devel- opments connected to object-oriented programming and related areas could be presented and discussed. Over the last few years object-oriented technology has gained widespread use and considerable popularity. In parallel with this, the field has matured scientifically, but there is still a lot of room for new ideas and for hot debates over fundamental issues, as these proceedings show. The 22 papers in this volume were selected by the programme committee from 129 submissions. Important issues discussed in the contributions are language design, specification, databases, concurrency types and software development.

This book constitutes the refereed proceedings of the 10th European Conference on Object-Oriented Programming, ECOOP '96, held in Linz, Austria, in July 1996. The 21 full papers included in revised version were selected from a total of 173 submissions, based on technical quality and originality criteria. The papers reflect the most advanced issues in the field of object-oriented programming and cover a wide range of current topics, including applications, programming languages, implementation, specification, distribution, databases, and design.

It is now more than twenty-five years since object-oriented programming was “inve- ed” (actually, more than thirty years since work on Simula started), but, by all accounts, it would appear as if object-oriented technology has only been “discovered” in the past ten years! When the first European Conference on Object-Oriented Programming was held in Paris in 1987, I think it was generally assumed that Object-Oriented Progr- ming, like Structured Programming, would quickly enter the vernacular, and that a c- ference on the subject would rapidly become superfluous. On the contrary, the range and impact of object-oriented approaches and methods continues to expand, and, - spite the inevitable oversell and hype, object-oriented technology has reached a level of scientific maturity that few could have foreseen ten years ago. Object-oriented technology also cuts across scientific cultural boundaries like p- haps no other field of computer science, as object-oriented concepts can be applied to virtually all the other areas and affect virtually all aspects of the software life cycle. (So, in retrospect, emphasizing just Programming in the name of the conference was perhaps somewhat short-sighted, but at least the acronym is pronounceable and easy to rem- ber!) This year’s ECOOP attracted 146 submissions from around the world - making the selection process even tougher than usual. The selected papers range in topic from programming language and database issues to analysis and design and reuse, and from experience reports to theoretical contributions.