The long term success of an organization depends significantly on its ability to properly evaluate the performance of its employees. The purpose of this study was to apply the method of self-evaluation to private and public Greek hospital employees, compare results, and assess the value of the methodology. A self-administered questionnaire was developed, administered, and completed by 21 employees of a private hospital and 25 employees of a public hospital. Data were recorded and analyzed in EXCEL 2008. Results showed that private hospital personnel gave higher ratings in all categories suggesting a leniency in their evaluation process and differing significantly from the evaluation of their managers. Public hospital personnel gave more realistic ratings of their performance and work environment but lower than what is reported in state official reviews of the performance of public health sector employees. Self-assessment is a useful tool because it provides insight into the employee’s perspective and understanding of the work environment. However, it is insufficient on its own because employees are not likely to exercise objective selfcriticism while their perceptions are often different from that of management. Hence, it is recommended that self-assessment is used in combination with a manager’s or a third-party evaluation for optimum results.