The purpose of this tutorial is to examine CMS's 53-Group Resource Utilization Group (RUG) classification system from both a high level and technical perspective. The participant will gain a better understanding of relationships between specific items from the Minimum Data Set (MDS) 2.0 and the RUG categories as well as how the underlying Case Mix Index (CMI) sets determine the actual per diem Medicare Part A payment level. A discussion of nursing indices associated with the respective RUG groups will provide background information for the important new CMS staff time measurement study which will impact payment levels in the future. The program concludes with the particulars of translating the RUG score recorded in the T3MDCR field of the MDS to the Medicare claim which requires a HIPPS modifier.