Since organizations exist to achieve goals, the degree of success that individual employees have in reaching their individual goals is important in determining organizational effectiveness. The assessment of how successful employees have been at meeting their individual goals, therefore, becomes a critical part of HRM. This leads us to the topic of performance appraisal. People differ in their abilities and aptitudes. These differences are natural to a great extent and cannot be eliminated even by giving the same basic education and training to them. There will be some differences in the quality and quantity of work done by different employees even on the same job. Therefore, it is necessary for management to know these differences so that the employees having better abilities may be rewarded and the wrong placements of employees may be rectified through transfers. The individual employee may also like to know the level of his performance in comparison to his fellow employees so that he may improve on it. Thus, there is a great need to have suitable performance appraisal system to measure the relative merit of each employee.