The aim of this study was to determine population norms and determinants of anxiety and depression in a population-based sample of 731 women with breast cancer (aged 23-60 years) with the Hospital Anxiety and Depression scale (HADS). The prevalence of 'probable' psychological morbidity due to anxiety was 23% and due to depression was 3%. When the women identified as 'possible' cases were included, the respective proportions were 45 and 12%. Higher anxiety was present in younger, less educated women not born in Australia. There was no clear pattern of risk factors for depression. These population-based findings highlight the need for clinicians to be aware that age, education and country of birth may identify a particularly vulnerable subgroup. While brief scales such as the HADS are limited in their ability to accurately predict a clinical diagnosis, high scores identify those who may warrant referral for clinical evaluation.