Technical Abstract: For some years the Beef Improvement Federation has discussed issues involved in multiple trait selection to improve profitability. Meanwhile, the pork industry has been quick to adopt selection index technology as a means to this end. Selection index technology depends on having in place a genetic evaluation system for economically important and indicator traits. The necessary extension beyond routine genetic evaluation is to derive relative economic values (partial derivatives of profit with respect to phenotypes) for biological traits determining differences between animals in their contribution to profitability. The perspective is necessarily long-term and customer focused. The problem is complex in that differences in production systems lead to differences in the relative economic values and therefore customized indexes for each producer. Experiences of a major pork producer in using selection index technology are used to highlight some important principles.