OBJECTIVE To determine whether applying the methodology of Evaluation and care quality improvement to the design of Clinical Procedures can obtain Procedure documents of high scientific-technical quality, from the structural point of view. METHODS A retrospective evaluation study lasting 3 years. METHODS The Barrio del Carmen Health Centre in Murcia. METHODS The Primary Care team. All those professionals with activities involving Procedure documents. METHODS The object of study is all the documentation of the Procedures produced between 1985 and 1993. The initial evaluation was in 1990. After the detection of deficiencies, corrective measures were proposed. In 1993 there was a re-evaluation, using the compliance scales of the quality of design criteria, which had been previously worked out on the basis both of the most important parts of the Bibliography and the quality specifications stated by the system's internal clients (the professionals). Measurements were made before and after intervention. RESULTS After the application of the corrective measures arising from the first evaluation, a significant improvement in all the design criteria for the procedures was obtained: the average defects per procedure document fell from 8.26 to 1.85. Three of the procedure documents ended up having no defects, either in structure or formal design (format, design method and document production). CONCLUSIONS A substantial improvement in the structural quality of the documents for the Procedures developed in our Health Centre was achieved by applying the methodology of evaluation and quality improvement.