The objectives of this study were: (1) to estimate the costs borne by families caring for patients with variant Creutzfeldt-Jakob disease (vCJD); (2) to contextualise results to recent policy initiatives, and (3) to consider the methodological problems of estimating costs of care. Semi-structured interviews and a follow-up postal questionnaire, eliciting costs to families both before and after the patient's death, were carried out. Participants included 19 families of patients with vCJD. Cost profiles were constructed, detailing key time and financial costs associated with their relative's illness and death accruing to families. Main outcome measures included total, median and ranges of relevant cost elements. Sensitivity analyses, comparing high and low cost estimates, were undertaken. The total time cost to families before patient's death ranged between 605 and 9230 hours (median 2006 hours). Applying low cost estimates, families incurred between pound 2616 and pound 39 588 (median pound 14 481) in forgone earnings and between pound 2699 and pound 18 558 (median pound 8049) in marginal sundry costs before the patient's death. The value of care provided by families ranged between pound 0 and pound 87 303 (median pound 9652) at low cost estimates. Many families continued to incur costs after the patient's death, with low cost estimates per week ranging between pound 0 and pound 176 (median pound 29). Costs to families associated with vCJD were substantial and greatly exceeded benefit entitlements. These costs were high even if patients received care in hospital, varied as the illness progressed and continued after patients' deaths. The National Carers Strategy does not consider fully the needs of some groups of carers or the full range or magnitude of potential costs to families associated with caring.