The primary objective of Phase I of this Contract is to develop a demonstration interface between the PROPHET II system of software tools for life science research and the Scop simulation software system. The long- term objective of the project is to make the powerful numerical simulation and optimization capabilities of Scop available to the PROPHET user through a transparent interface in the PROPHET style. In Phase I, Scop will be coupled to PROPHET II through a simple text-passing interface, maintaining the standard appearance of Scop easily installable with PROPHET II, 2) any required additions or modifications to the PROPHET II code, 3) documentation of the design of the demonstration interface and the Scop capabilities made available through PROPHET II< and 4) preliminary ideas for the design of the Phase II transparent interface. Simulation is a powerful tool for understanding the characteristics of complex biomedical systems, from chemical reactions to populations. By expanding the simulation capabilities available in PROPHET II, this project thus has the potential of making significant contributions to research in biochemistry, physiology, pharmacology, toxicology, epidemiology, and other biomedical fields.