This article provides an overview of cancer in Canada in 1984, including an analysis of geographic patterns by province. Trends for selected sites of cancer incidence from 1970 to 1984 and cancer mortality from 1970 to 1987 are also examined. Finally, trends since 1970 in cancer incidence and mortality are examined in the context of strategies for cancer control. Because of the need to assemble cancer information from a variety of sources within each province and territory, several years elapse between cancer diagnosis and the compilation of national figures. Still, the year-to-year analysis of incidence data in this article provides valuable information of cancer trends. In recent years, considerable improvements in Canada's system of cancer registration have led to improved consistency among provinces for both age-standardized rates and mortality/incidence ratios.