Increasing pressure of competition together with rapid technological changes is forcing companies to introduce shiftwork for the first time, or to arrange existing shift systems more efficiently. The main trends to be seen are towards an extension of operating hours and towards more flexible adjustments to fluctuations in demand. These trends seem bound to continue in the coming years. This book intends to show the challenges for both shiftwork research and practice at the beginning of the 21st Century. One of the major tasks for shiftwork research is to analyse the possible negative effects on those working in these new shift systems and to provide support by means of adequate, innovative concepts. The task of practitioners is to improve working conditions for shift workers according to latest scientific knowledge.