IT IS SUGGESTED THAT MANY OF THE PROBLEMS EVALUATION FACES STEMS FROM A FUNDAMENTAL MISAPPREHENSION OF WHAT EVALUATION IS AND OF WHAT IT CAN AND SHOULD DO. DISCUSSED ARE THE ROLE, TO DATE, OF SYSTEMATIC, QUANTITATIVE THINKING IN THE EVALUATION OF GOVERNMENTAL PROGRAMS AND POSSIBLE REASONS FOR THE 'DISAPPOINTING' INITIAL RECORD OF THE PLANNING, PROGRAMMING, BUDGETING SYSTEM (PPBS). A REVIEW OF THE PREVAILING CONCEPTIONS OF EVALUATION IS FOLLOWED BY A DETAILED VERBAL AND MATHEMATICAL OUTLINE OF THE WAY IN WHICH EVALUATIONS SHOULD SERVE THE GOVERNMENT. CONSIDERATION OF THE PROBLEMS THAT EVALUATION FACES WITHIN AN ORGANIZATIONAL ENVIRONMENT PLACES EMPHASIS ON DESCRIBING THE INTERACTIONS AMONG DIFFERING INTERESTS WHICH HAMPER THE ABILITY OF EVALUATION TO ASSIST DECISION MAKERS. THESE ISSUES ARE THEN APPLIED TO A CASE STUDY OF AN ACTUAL EVALUATION OF A PARTIALLY U.S. FUNDED BIO-MEDICAL RESEARCH PROGRAM IN YUGOSLAVIA. THE ULTIMATE EXPLANATION FOR THE RELATIVE LACK OF SUCCESS OF THIS STUDY IS ATTRIBUTED TO THE BASIC MISCONCEPTION OF THE EVALUATIVE FUNCTION. THE FINAL CHAPTER MARSHALS ARGUMENTS FOR ALL THE POLICY PRESCRIPTIONS PUT FORWARD AND DISCUSSES OPPOSING RECOMMENDATIONS. A SELECTED BIBLIOGRAPHY AND AN INDEX ARE INCLUDED.