An aging population, new technologies and drugs, and tightening constraints on financial and human resources have placed increased demands on hospitals to meet health care needs. Canadian hospitals, health regions, and ministries are placing a high priority on the evaluation of appropriateness and efficiency of medical care and on the proactive and targeted reduction of inefficiencies. The CMG+ grouping methodology is a case mix tool produced by the Canadian Institute for Health Information (CIHI) to analyze the acute-care inpatient population in Canada. CMG+ methodology can be applied, for example, to utilization management. The expected length of stay (ELOS) indicator can be used as a benchmark for assessing the length-of-stay distribution of various subgroups of patient activity. It can also be used to compute potentially conservable days and to identify those patient subgroups where gains in efficiency may be realized. We describe CMG+ utilization management using this and other examples.