Of the 24 069 women aged 45-64 registered with a Practitioner in the South West Surrey Health District 69% attended for breast cancer screening by clinical examination and mammography, with the resultant cancer detection rate of 5.5/1000 women screened and a cancer: benign biopsy rate of 1:1.77. These cancers represent 94% of cancers diagnosed in screened women and 84% of all cancers diagnosed in the total population of this age within one year of the screening invitation. Seventy-three percent of the cancers detected by screening and 66% of all cancers diagnosed in the total population within a year of the screening invitation were 2 cm (or less) in maximum diameter.