Stephen Walter received his Ph.D. from the University of Edinburgh, Scotland, under the supervision of Professor D. J. Finney in 1972. After faculty appointments at the University of Ottawa (3 years) and Yale University School of Public Health (7 years), he joined the Department of Clinical Epidemiology and Biostatistics at McMaster University, where he is now a Professor.

 Dr Walter collaborates with clinicians in internal medicine, evidence-based medicine, and developmental pediatrics, and with epidemiologists working in environmental health, cancer etiology and screening. He is interested in several areas of biostatistical methodology, including: risk assessment and communication; evaluation of diagnostic and screening data; regional and temporal variation in health; and design and analysis of medical research studies. Collaborative work with clinicians and other scientists has always been a hallmark of Dr Walter's research. As well as groups in Canada, Dr Walter has collaborated with researchers in India, Australia and Finland among others. He has also been highly influential in working with international bodies such as the World Health Organization dealing with global health issues. One area in which his impact has been widely felt is in screening for disease. His recent reports on screening for cervical cancer are one of the most important clinical and public health developments at present, particularly in developing countries.