Abstract This paper presents a concurrent extension of prolog called cs-prolog ∗ ∗ cs-prolog is a joint development between Multilogic Computing Ltd, Brainware Gmbh and Densitron Computers (Communicating Sequential prolog) which explicitly involves the concept of communicating sequential processes and is intended to be implemented on distributed (nonshared memory) parallel computers, mainly on transputer networks. cs-prolog can also be considered as a distributed simulation language. First, an informal introduction to cs-prolog summarizes the main features of the language. The power of the language is illustrated by solving some simple problems. The scheduling principles of cs-prolog on single transputers and on multiple transputer systems are described in detail. The cs-prolog distributed backtracking algorithm is defined and the details of distributed implementation on multitransputer systems are explored. cs-prolog is currently available on monoputers and multiputers connected to PC-compatible hosts.