CSP (Communicating Sequential Processes) is a notation proposed by Hoare, for expressing process communication and synchronization. Although this notation has been widely acclaimed, Hoare himself never implemented it as a computer language. He did however produce the necessary correctness proofs and subsequently the notation has been adopted (in various guises) by the designers of other concurrent languages such as Ada and occam. Only two attempts have been made at a direct and precise implementation of CSP. With closer scrutiny, even these implementations are found to deviate from the specifications expounded by Hoare, and in so doing restrict the original proposal. This thesis comprises two main sections. The first of these includes a brief look at the primitives of concurrent programming, followed by a comparative study of the existing adaptations of CSP and other message passing languages. The latter section is devoted to a description of the author's attempt at an original implementation of the notation. The result of this attempt is the creation of the CSP-i language and a suitable environment for executing CSP-i programs on an IBM PC. The CSP-i implementation is comparable with other concurrent systems presently available. In some aspects, the primitives featured in CSP-i provide the user with a more efficient and concise notation for expressing concurrent algorithms than several other message-based languages, notably occam. / KMBT_363 / Adobe Acrobat 9.53 Paper Capture Plug-in