Medicare has paid skilled nursing facilities (SNFs) using a prospective payment system (PPS) since 1998. This report offers policy options to refine Medicares payment of SNF services by developing alternative patient classification models. Three models classify patients according to expected non-therapy ancillary (NTA) costs: two models use data from the SNF to model NTA costs; a third adds data from prior hospital stays. A fourth model predicts rehabilitation therapy costs using patient characteristics. The fifth uses Diagnostic Related Groups to predict total SNF care costs. The report also simulates options for outlier payments for exceptionally high-cost cases.