A brief history of manufacturing control systems. A personal view of where we went wrong. Part 4This series of four articles traces the history of manufacturing control systems; showing where we went wrong; what we are still doing wrong; and what companies, who have relied heavily on systems solutions, can do to regain their competitiveness. Part 4 looks at World Class Manufacturing Techniques (JIT, TQM, Cellular Manufacturing, etc.) together with Activity Based Management.