About 8000 more cases of tuberculosis were notified in the years 1988 to 1993 than would have been expected if previous trends had continued (95% confidence interval (CI) 3000-12,000). Tuberculosis notifications were analysed to determine the population groups and geographical areas in which increases occurred. Increases were greatest in regional health authorities (RHAs) with large conurbations, while rates generally continued to decline in RHAs that serve more rural areas. The rate of notification rose significantly in males aged 15 to 34 years and fell in men over 35. In females, the rate increased only in the 35 to 64 year age group. Non-respiratory tuberculosis accounted for 21% of notifications in 1987 and 27% in 1993. In most age, sex, and geographical groups significant increases were confined to non-respiratory tuberculosis, but the rate of both respiratory and non-respiratory tuberculosis rose in males aged 15 to 34 years in North Thames RHAs. A number of factors may have contributed to the observed increase. Reporting of cases may have improved following the appointment of consultants in communicable disease control in 1988, whose role includes improving notification practices. Such improvements might explain the increased proportion of notifications of non-respiratory tuberculosis, as this may have been undernotified to a greater extent than respiratory tuberculosis in the past. Other factors associated with recent increases are discussed.