During the period 1986-2001, a metastasised basal-cell carcinoma of the head was diagnosed in five patients (a 35-year-old woman and four men aged 40, 44, 54 and 54 years) at the Utrecht University Medical Centre, the Netherlands. Metastases were found in the cervical lymph nodes, the skeleton, the parotid region and the lungs. The tumours were all of the morphoeic or 'wispy' type. The treatment consisted of excision and sometimes radiotherapy. Two patients died, one of whom of a cause unrelated to the tumour, two patients were free of symptoms 24 months after the last treatment and one patient was still being treated with radiotherapy. It is often assumed that basal-cell carcinomas do not metastasised, but a frequency of 0.0028-0.55% is reported in the literature. An important risk factor is the size of the tumour. Surgical excision or Mohs' micrographic surgery is the preferred method of treatment because this allows histological inspection of the excised margins. Due to the low incidence, there are no clear therapeutic guidelines for the treatment of patients with metastasised basal-cell carcinoma.