ACP, the Algebra of Communicating Processes, is an algebraic approach to
the study of concurrent processes, initiated by Jan Bergstra and Jan
Will em Klop in the early eighties. These proceedings comprise the
contributions to ACP94, the first workshop devoted to ACP. The work-
shop was held at Utrecht University, 16-17 May 1994. These proceedings
are meant to provide an overview of current research in the area of ACP.
They contain fifteen contributions. The first one is a classical paper
on ACP by J.A. Bergstra and J.W. Klop: The Algebra of Recursively
Defined Processes and the Algebra of Regular Processes, Report IW
235/83, Mathematical Centre, Amsterdam, 1983. It serves as an
introduction to the remainder of the proceedings and, indeed, as a
general introduction to ACP. An extended abstract of this paper is
published under the same title in the ICALP' 84 proceedings. Of the re-
maining contributions, three were submitted by the invited speakers and
the others were selected by the programme committee. As for the
presentations, Jos Baeten, Rob van Glabbeek, Jan Friso Groote, and Frits
Vaandrager were each invited to deliver a lecture. A paper relating to
Frits Vaandrager's lecture has already been submitted for publication
elsewhere and is not, therefore, included in these pro- ceedings.
Gabriel Ciobanu, one of our guests, gave an impression of his work in an
extra lecture. Furthermore, ten presentations were given on the basis of
selected papers.