This study aimed to examine the extent and determinants of patient and general practitioner delay in the presentation of breast cancer. One hundred and eighty-five cancer patients attending a breast unit were interviewed 2 months after diagnosis. The main outcome measures were patient delay in presentation to the general practitioner and non-referral by the general practitioner to hospital after the patient's first visit. Nineteen per cent of patients delayed > or = 12 weeks. Patient delay was related to clinical tumour size > or = 4 cm (P = 0.0002) and with a higher incidence of locally advanced and metastatic disease (P = 0.01). A number of factors predicted patient delay: initial breast symptom(s) that did not include a lump (OR 4.5, P = 0.003), not disclosing discovery of the breast symptom immediately to someone else (OR 6.0, P < 0.001), seeking help only after being prompted by others (OR 4.4, P = 0.007) and presenting to the general practitioner with a non-breast problem (OR 3.5, P = 0.03). Eighty-three per cent of patients were referred to hospital directly after their first general practitioner visit. Presenting to the GP with a breast symptom that did not include a lump independently predicted general practitioner delay (OR 3.6, P = 0.002). In view of the increasing evidence that delay adversely affects survival, a large multicentre study is now warranted to confirm these findings that may have implications for public and medical education.