Premature cancer mortality trends were examined by reviewing cumulative mortality risk ('cumulative risk' hereafter) and potential years of life lost (PYLL) up to and including 64 years of age between 1953 and 2002 in Ireland. Trends were assessed quantitatively by Joinpoint analysis of both measures (with PYLL expressed as an age-standardized rate). The age of 64 years was used for these summary measures to reflect the focus of the Irish Government's cancer strategy on cancer in the under-65 population. Some differences emerged when ranking the significant types of cancer using cumulative risk and PYLL values. In general, however, the two methods generated similar overall trends, although PYLL rates tended to show steeper or longer-term declines, presumably reflecting the greater weight given to deaths at younger ages. Most cancers have, in recent years, shown a downward, or levelling-off of, trend for both sexes. The only exceptions were significant increases for oesophageal cancer in men (both measures), and prostate cancer (cumulative risk), cervical cancer (PYLL rate) and lymphoma in both sexes (cumulative risk). Rankings based on both cumulative risk and PYLL showed that male lung cancer is still the leading cause of premature death from cancer in Ireland, despite recent falls in mortality rates. Breast cancer has consistently been the leading cause of premature cancer death in women since the 1950s. Stomach cancer was once the second leading cause of premature cancer death in women, but since the 1960s it has been replaced by lung cancer. Ovarian cancer, having had a middle ranking for many years has, since the early 1990s, become the third leading cause of premature cancer death for women.