The objective of this project is to develop a set of tools to evaluate performance differences among several nurse staffing systems. The tools will consist of a set of computer simulation programs. The program structure and inputs form the following independent variables: workload variation, workload level, nursing care staff available, ward structure, and one of four possible Master Nurse Staffing Patterns. Program outputs (dependent variables) include wage costs, frequency of understaffing and overstaffing, and degree of understaffing and overstaffing. The program will also measure the number of nurses floated into and out of each ward for staffing systems which require nurses to float among wards. The research method is the Matched Sample Posttest-Only Design. Computer simulation is the method employed to achieve perfect matching of independent variables, and control of extraneous variables. Small hospital (100 beds in 4 wards) pilot simulations have been successfully completed usig a mainframe computer. Phase I will determine the feasibility of applying this methodology to the study of larger institutions (400 or more beds), and the likelihood of using microcomputers for the commercial application. Mainframe computers are not generally available to nurse managers. Therefore, Phase II will require a major reprogramming effort so the simulations can be run on a microcomputer. The final product will be an innovative decision support tool which can be marketed to hospitals, nursing homes, and other multi-ward health care institutions.