This text guides the reader through the many forms of shiftwork, adopting a broad definition as being any regularly-taken employment outside the "day working window" 06.00 to 18.00. Topics covered include human, biological, economic, social and domestic influences; stress, strain and shiftwork; health and safety; shiftwork and task performance.

Timothy H. Monk has been engaged in researching the human biological clock and its influences on sleep and performance since 1974. H is currently an Associate Professor pf Psychiatry and Director of the Human Chronobiology Program at the University of Pittsburgh School of Medicine.

Simon Folkard has been working in chrono psychology since 1971. He currently leads the Body Rhythm and Shiftwork Team at the Medical Research |Council's Applied Psychology Unit in Sheffield, UK.

Sleep and the biological clock; social challenges to the shift worker; stress and strain; health consequences; performance and safety consequences; inter-individual differences; coping strategies for the worker; strategies for the employer.