Human Performance Improvement: Building Practitioner Performance - Paperbackby William J. Rothwell (Author), Carolyn K. Hohne (Author), Stephen B. King (Author) Organizations are under pressure to build and sustain competitive advantage with and through people. For that reason, managers continue to demand results from workers and look for as many ways as possible to increase productivity and decrease the costs of doing business. Human performance improvement (HPI) is a systematic approach to securing better performance from