THOMAS F. WALLACE has spent his career writing, teaching, and helping manufacturing enterprises to operate better. He is currently a Distinguished Fellow of The Ohio State University's Center for Excellence in Manufacturing Management. MICHAEL H. KREMZAR recently retired from his position as Vice President of Product Supply at Procter & Gamble, where he worked for nearly forty years. During that time he was a catalyst and leader in P&G's highly successful implementation of global ERP.