Using the accumulated data on deaths from mesothelial tumours among cohorts of male and female factory workers at a London asbestos textile factory, the mortality from this cause up to the year 2000 AD has been predicted. The limitations of the methods used are pointed out, but it is estimated that for men the mortality due to mesothelial tumours will be between 7% and 11% of the total mortality and somewhat higher for women. The highest number of deaths from mesothelial tumours will occur during the 1980s, thereafter the numbers will decline because of the decreasing size of the cohort resulting from general mortality.