This study describes a new clinical tool for needs assessment in palliative care: the Problems and Needs in Palliative Care questionnaire (PNPC). It was developed to support the provision of care tailored to the specific demands of patients, which only can be provided when their needs are clearly identified. To test validity and reliability, 64 patients with metastatic cancer living at home completed the PNPC. Of 140 initial items, 2 were deleted because of low response. No important topics were missing. Dimensions were proposed to organize the problems and needs in a logical and practical array for use in individual patients, and to enable statistical analysis of patient-groups. Reliability analysis supported the proposed dimensions, with Cronbach's alpha coefficient >0.70 for dimensions with > or = 5 items, and alpha >0.65 for the 3- and 4-item dimensions. However, the dimensions 'physical symptoms' and 'social issues' lacked coherency with some low item-total correlations. The PNPC demonstrated convergent validity with the European Organization for Research and Treatment of Cancer (EORTC) and COOP-WONCA quality-of-life measures. These data are a first step in validating the PNPC, although the 'social issues' dimension needs reconsideration. Further studies are needed to evaluate clinical use.