New developments in the NIOSH life table analysis system (LTAS) were discussed. The system, developed in the 1970s, is a series of computer programs designed to analyze data obtained in occupational cohort studies. The original system could calculate person years at risk for the cohort stratified by age, race, sex, calendar time, duration of exposure, and time since first hire, analyze up to 99 work histories for each subject, allocate observed deaths from specific causes in the International Classification of Disease codes into appropriate NIOSH death categories, and calculate standard mortality ratios for each NIOSH death category. Improvements added to the original system included providing the capability to produce a cohort status report, an LTAS run parameter report, and an LTAS exceptions report and the ability to compute proportionate mortality and proportionate cancer mortality ratios. Expected United States (US) death rates stratified by sex, race, and 5 year age and calendar period were created for the period 1940 to 1989. Newest developments consist of providing the system with a means of directly standardizing death rates for each exposure category, detecting linear trends across exposure categories, and lagging exposures. Multiple cause of death rate files for the US based on contributory as well as underlying causes of deaths for the period 1965 to 1984 have been created in collaboration with the National Cancer Institute. A user friendly personal computer version of the LTAS was under development.