RESUMEN
Nowadays, downsizing the government to have an effective and flexible organization is considered to be government's top priority in the world and outsourcing is one of the ways to achieve this goal. Accordingly, Shahid Beheshti University of Medical Sciences has delegated some of its hospitals' duties to the private sectors. The present study has been carried out to assess the performance of outsourced clinical laboratories. This Descriptive Evaluation study was carried out during 6 month [May 2011 till February 2012]. The data was collected by two questionnaires with close-ended questions and one with open-ended questions, and analyzed by Wilcoxon, using SPSS software. There is an improvement in outsourcing laboratory services. For example, increase in the number of tests [32%] and in the type of tests [37%]. Consequently, increase of hospital income [51%]. The number of personnel is decreased and their responsibility and behavior are improved. Overall, it seems that outsourcing laboratory program could achieve its major goals such as: Absorbing non-governmental resources in both administrative and financial aspects, omitting extra expenditure, acquiring benefits, and upgrading productivity of laboratories