These foci, in turn, reflected changing perspectives and priorities among researchers and practitioners regarding the purposes and strengths of the performance appraisal formats and the possibilities of enhancing the formats so that they demonstrate ever-enhanced reliability, validity and accuracy. In each phase, those who developed the formats and sought out their effectiveness, tended to highlight one major aspect or focus pertaining to the efficacy of the formats. In order to gain a greater appreciation and understanding of the lack of finality regarding this question, this chapter indicates that several phases in the historical development of performance appraisal can be identified. In reality, over a period of many years, researchers attempted to describe the process that leads to effective performance evaluation but arrived at no conclusive finding. Section I - An Historical Retrospective: Having reviewed the different approaches to performance appraisal systems PASs, it would seem a relatively simple matter to establish which of the various formats actually best succeeds to achieve the goals of performance appraisal to the highest degree. Performance appraisal and beyond: Directions for future research and application.Performance appraisal: The outlook and future directions.Beyond performance appraisal: To performance management and firm-level performance.Where are performance appraisals headed? The debate from a business perspective.Ways to improve the performance appraisal system 2: Alternative strategies for assessing and evaluating performance.Ways to improve the performance appraisal system 1: Rater training.External environment factors influencing the appraisal process.Performance appraisal and political considerations in the workplace.Organizational environment factors influencing the appraisal process.Effectiveness of performance evaluation formats.Performance at work and its appraisal: Demarcation of the field.Encyclopedia of Tourism Management and Marketing.Elgar Encyclopedia of International Economic Law.Elgar Encyclopedia of Environmental Law.Encyclopedia of Law and Economics, 2nd Edition.Encyclopedia of Private International Law.