### ATAL: A Five Year Retrospective

##### Michael Wooldridge and Nicholas R. Jennings
October 1998

On the occassion of the fifth birthday of ATAL, Mike Wooldridge and Nick Jennings (the organisers of the first workshop) wrote a short retrospective on the workshop, describing the goals of the workshop, and how the original vision had matured over the years. This was published as a preface to the proceedings of ATAL-98.

The leading-edge of computer science research is notoriously fickle. New trends come and go with alarming and unfailing regularity. In such a rapidly changing field, the fact that research interest in a subject lasts more than a year is worthy of note. The fact that, after five years, interest not only remains, but actually continues to grow is highly unusual. As 1998 marked the fifth birthday of the International Workshop on Agent Theories, Architectures, and Languages (ATAL), it seemed appropriate for the organisers of the original workshop to coment on this remarkable growth, and reflect on how the field has developed and matured.

The first ATAL workshop was co-located with the Eleventh European Conference on Artificial Intelligence (ECAI-94), which was held in Amsterdam. The fact that we chose an AI conference to co-locate with is telling: at that time, we expected most researchers with an interest in agents to come from the AI community. The workshop, which was planned over the summer of 1993, attracted 32 submissions, and was attended by 55 people. ATAL was the largest workshop at ECAI-94, and the clear enthusiasm on behalf of the community made the decision to hold another ATAL workshop simple. The ATAL-94 proceedings were formally published in January 1995 under the title Intelligent Agents, and included an extensive review article, a glossary, a list of key agent systems, and --- unusually for the proceedings of an academic workshop --- a full subject index. The high scientific and production values embodied by the ATAL-94 proceedings appear to have been recognised by the community, and resulted in ATAL proceedings being the most successful sequence of books published in Springer-Verlag's Lecture Notes in Artificial Intelligence series.

ATAL-95 was held at the International Joint Conference on AI, which in 1995 was held in Montreal, Canada. The number of submissions leapt to 55, and the workshop was attended by 70 people. Since many international conferences fail to attract this many submissions and delegates, it was decided at this point to make ATAL an annual event. It was also decided to hold ATAL-96 in Europe, following the successful model of ATAL-94 by co-locating with ECAI-96, which was held in Budapest, Hungary. We received 56 submissions, and the workshop was attended by about 60 delegates. For ATAL-97, it was felt that the workshop was sufficiently mature that it merited its own event, and so the conference was located immediately before the AAAI-97 conference in Providence, Rhode Island. It was attended by about 75 delegates. ATAL-98 was co-located with the Agents World'' series of events, held in Paris in July 1998. About 90 submissions were received, and 120 delegates registered for ATAL.

In the five years since ATAL-94, the landscape of the computing world has changed almost beyond recognition. Even seasoned veterans of the historically fast-moving IT environment have been surprised by the current rate of change. Perhaps the simplest way we can sum up these changes is by noting that the first ATAL was also the last not to have a World-Wide Web (WWW) page. In 1999, on the eve of the new millenium, it would be unthinkable for a serious academic conference or workshop not to have a dedicated WWW site. The changes brought about by the explosion of the Internet into world-wide public and corporate awareness are well-documented, and it is not appropriate for us to add to the mountain of comment (and hyperbole). However, it is important to note that the rise of the Internet had a significant impact on the development of the agent field itself. By the summer of 1994 it was becoming clear that the Internet would be a major proving ground for agent technology (perhaps even the killer application''), although the full extent of this interest was not yet apparent.

The emergence of agents on and for the Internet gave rise to a new, associated software technology, somewhat distinct from the mainstream'' of agent research and development. In the summer of 1994, a California-based company called General Magic was creating intense interest in the idea of mobile agents --- programs that could transmit themselves across an electronic network and recommence execution at a remote site. At the time, General Magic were distributing a widely-read white paper that described Telescript'' --- a programming language intended to realise the vision of mobile agents. In the event, it was not Telescript, but another programming language that caught the imagination of the Internet community: Java. When Netscape incorporated a Java virtual machine into their Navigator browser, and hence brought the idea of applets into the mainstream, they gave Java an enormous impetus, both as a way of animating the Internet, but also as a powerful, well-designed object-oriented programming language in its own right. A number of mobile agent frameworks were rapidly developed and released as Java packages, and interest in Telescript rapidly waned. As we write this preface in late 1998, Java is the programming language of choice not just for agent systems, but also, it seems, for most other applications in computing.

Mobile agent technology was not the only other agent technology beginning to make its presence felt at the time of the first ATAL. The summer of 1994 saw the publication of a special issue of {\em Communications of the ACM with the title intelligent agents''. Many of the articles in this special issue described a new type of agent system, that acted as a kind of expert assistant'' to a user working with a particular class of application. The vision of agents as intelligent assistants was perhaps articulated most clearly by Pattie Maes from MIT Media Lab, who described a number of prototype systems to realise the vision. Such user interface agents rapidly caught the imagination of a wider community, and in particular, the commercial possibilities of such technologies was self-evident. A number of agent startup companies were founded to commercialise this technology (many of which have by now either been sold or gone bust). Current interest in such agents comes, to a great extent, from the possibility of using them in electronic commerce scenarios, where they negotiate on behalf of their owner''.

The commercial interest in agents in the latter half of the 1990s has not been limited to venture capitalists and small scale'' agent systems. Perhaps one of the most encouraging long-term trends for agent technology is the idea of agents as a software engineering paradigm. The level of interest in this concept has been evidenced in several ways. For example, the number of large-scale industrial-strength agent systems being developed and deployed is an obvious indicator. However, the degree of interest is perhaps best illustrated by the attempts currently underway to develop international standards for agent communication. Although some tentative steps towards standard agent communication languages were taken by the KQML/KIF community in the USA in the early 1990s, it is the FIPA initiative, started in 1995, which currently appears to be the best candidate for a standard agent communication framework.

Turning more specifically to the ATAL workshops, a number of smaller scale trends have emerged, echoing to some extent the more visible changes in the computing world itself. One obvious indicator that agent technology is beginning to mature is that far fewer new agent architectures are being developed. It seems that authors are taking architectures off the shelf, rather than developing their own. In this vein, the belief-desire-intention (BDI) class of architectures has become particularly prominent. This work represents a paradigm example of the ATAL ethos --- there is a well-defined theory, which relates more or less directly to specific architectures or programming languages. On the theoretical side, there has been an increasing trend towards more integrated models; that is, theories which cover a wider proportion of an agent's decision making and acting capabilities.

We noted above that five years sometimes seems like a long time for an academic workshop. Incredibly, when ATAL began, there were no conferences dedicated to agent technology. In contrast, the agent research community is now served by at least two major international scientific conferences (the International Conference on Multi-Agent Systems and the International Conference on Autonomous Agents), as well as a dedicated journal (Autonomous Agents and Multi-Agent Systems). That agent technology is able to comfortably support this degree of interest tells us that agents have a good chance of succeeding as a technology. We hope that ATAL will continue to play its part in this development, maintaining its current high level of scientific and production values, and serving a vibrant, rich research and development community.

To close, we would like to take this opportunity to thank those who have made ATAL the success we sincerely believe it is today. In particular, our thanks go to Joerg Mueller, Munindar Singh, Anand Rao, and Milind Tambe, who have all acted as organisers for ATAL, and helped to shape it through their dedication and vision. In addition, we would like to thank those who have played various other special roles throughout the first five years, including Klaus Fischer, Michael Fisher, Mike Georgeff, Piotr Gmytrasiewicz, David Kinny, and Jan Treur. Also thanks to the program committee members, and finally, to Alfred Hofmann, our editor at Springer-Verlag, whose support and genuine enthusiasm for a well-produced volume has helped establish ATAL as a premier forum for publishing agent research.

Send questions and comments to Tom Wagner at wagner@umcs.maine.edu.