This collection of presentations is from the mini-symposium entitled "Systems Science and Health: Using Analytical Approaches to Evaluate Healthcare Policy Decisions." The focus of this symposium is on systems science applications to health research. Systems science is a collection of analytical computer simulation techniques which are used to evaluate optimize and improve healthcare delivery processes. These techniques account for the complexity of the healthcare system and healthcare processes by modeling nonlinear relationships between variables, the feedback effects, delays and soft variables. The analysis stresses heterogeneity of agents, resistance to change, potential unintended consequences, and behavioral emergence in complex systems. Such models use historical data to simulate the operations of healthcare systems providing an approximation of future outcomes. The presenters will discuss several different types of simulations methods, highlight recent advances, and describe funding opportunities from the National Institutes of Health. Examples from chronic disease patient chains, physician incentive redesign, clinic staffing and Emergency Department redesign will be discussed.