As patients have become older their care needs have increased, and this has consequences for the work conditions within primary health care. Objectives: The aim of this study was to evaluate, whether the OPC instrument, which has been developed for hospital care, is valid and useful within primary healthcare for older people. Materials and Methods: Reliability and validity testing of the OPC instrument was carried out at a health care centre in Eastern Finland spring 2004. A total number of 92 questionnaires were handed out, and the response rate was 67% (n=61) in order to test the validity. The inter-rater reliability was tested through parallel classification. A total number of 860 patient's were classified; in total 1722 classifications were done. Cohens Kappa was chosen as the measurement for the consensus between the nurses' classification. Results: The consensus of the NI scores in total (OPC points) was 71%. The consensus measured with Kappa (k) showed a strong (0.65) consensus degree. Discussion: It can be said that the OPC instrument achieved a high enough reliability and validity in order to be seen as a reliable and useful instrument to measure the NCI within primary healthcare for the elderly. Conclusion: The OPC instrument can be seen as providing a fairly comprehensive view of the patient's caring needs, without claiming to be covering everything.