The explosion of java over the last year has been driven largely by its in role in bringing a new generation of interactive web pages to World Wide Web. Undoubtedly various features of the languages-compactness, byte code portability, security, and so on—make it particularly attractive as an implementation languages for applets embedded in web pages. But it is clear that the ambition of the Java development team go well beyond enhancing the functionality of HTML documents. “Java is designed to meet the chalanges of application development on the context of heterogeneous, network-wide distributed environments. Paramaount amoung these chalanges is secure delivery of applications that consume the minimum of systems resources, can run on any hardware and software platform, can be extended dynamically.” Several of these concerns are mirrored in developments in the High Prerformance Computing world over a number of years. A decade ago the focus of interest in the parallel computing community was on parallel hardware. A parallel computer was typically built from specialized processers through a proprietary high-performance communication switch. If the machine also had to be programmed in a proprietary language, that was an acceptable price for the benefits of using a supercomputer. This attitude was not sustainable as one parallel architecture gave way to another, and cost of porting software became exorbitant. For several years now, portability across platforms had been a central concern in parallel computing. HPJava is a programming language extended from Java to support parallel programming, especially (but not exclusively) data parallel programming on message passing and distributed memory systems, from multi-processor systems to workstation clusters.