Blood donation is indispensable for quality health service provision. The stagnation of the number of donations in Catalonia prompted up an external evaluation of the system of blood collection that could orient the future policies. An evaluation of blood-donor services in Catalonia was designed adopting a qualitative methodology. The evaluation design included the use of a variety of techniques namely participant observation, individual interviews, group interviews and documentary techniques. The field work was carried out in all blood-donation sectors of Catalonia from the 23th November to the 4th December, 1998. Using Atlas/ti, a computer science tool for the qualitative analysis of textual data, the information analysis partially followed the prescriptions of "grounded theory" and of some modalities of thematic content analysis. The results show the basic characteristics and deficiencies of the process and its organization, describing their strong and weak points. The findings also detail arguments on blood donation that the agents implied in the process, donors an professionals, use. We also report what reasons the blood-donor service managers/providers gave for donating blood, and what perceptions they had of blood donors.