The Netherlands breast cancer screening programme for women aged 50-75 years was gradually implemented during 1989-1997. Short-term indicators for this mammography screening are 80% attendance (800 000 examinations yearly), and for the subsequent screening examinations 7.4 referrals for clinical assessment per 1000 women screened, 4.7 biopsies and 3.6 breast cancers detected. Breast cancer mortality in The Netherlands has been decreasing since 1997 after having been stable for decades. The challenge now is to disentangle the relative contributions of mammographic screening, earlier clinical diagnosis, less aggressive tumours, treatment advances and risk factors towards this decline.