EVALUATIVE RESEARCH REQUIRES AN OPEN AND RESPONSIVE TYPE OF METHODOLOGY WHICH IS CLEARLY DEFINED AND RELEVANT TO THE CIRCUMSTANCES TO WHICH IT IS BEING APPLIED. IN ADDITION TO A REVIEW OF PERSONAL FACTORS, CERTAIN VARIABLES ARE IDENTIFIED TO STUDY THE PROBLEM OF DEVELOPING AN EFFECTIVE EVALUATION RESEARCH MODEL: ASSESSMENT OF THE PROBLEM; THE BASIC DESIGN INVOLVING IDENTIFICATION AND STIPULATION OF THE RESEARCH STRATEGY; THE TYPE OF RESEARCH STAFF; TECHNIQUES FOR DATA COLLECTION; AND THE REPORTING OF RESULTS. A SERIES OF FOUR CASE STUDIES IS PRESENTED CONTAINING SITUATION DESCRIPTIONS AND DISCUSSIONS OF APPROACHES TO THE DEFINED VARIABLES. THE CASES INCLUDE EVALUATIVE RESEARCH ON REHABILITATIVE TREATMENT METHODS WITH CHILDREN, CONCEPT ATTAINMENT IN CHILDREN ATTENDING A HEAD START PROGRAM, EFFECTIVENESS OF AN EMPLOYMENT PROGRAM FOR JUVENILE DELINQUENTS, AND EFFECTS OF FOSTER-PARENT TRAINING ON PERSONNEL OF A FAMILY SERVICES AGENCY. CERTAIN CHARACTERISTICS WHICH ARE USEFUL IN THE PROCESS-OUTCOME MODEL FOR EVALUATIVE RESEARCH ARE IDENTIFIED IN THE EXAMINATION PROCESS. A TRUST RELATIONSHIP MUST BE DEVELOPED WITH THE AGENCY OR PROGRAM STAFF BEFORE ENTERING INTO A STUDY SITUATION, AND THERE MUST BE A BONDING BETWEEN THE RESEARCH AND THE PROGRAM. CRITERIA SHOULD BE SELECTED TO INSURE RELEVANCE TO THE PROGRAM STAFF, AND MULTIMEASURES MUST BE USED WITH THE CRITERIA OR DEPENDENT VARIABLES. THE RESEARCH DESIGN SHOULD ALWAYS BE SHAPED TO FIT THE PROGRAM OR AGENCY STYLE; RESEARCH AIDES SHOULD BE UTILIZED IN RELATION TO THE STUDY SITUATION. OTHER NECESSARY CHARACTERISTICS IDENTIFIED ARE PERIODIC MEASUREMENTS DURING THE PROGRAM LIFE, CROSS-SECTIONAL MEASUREMENTS OF DIFFERENT PROGRAM ASPECTS, PERIODIC RESPONSE OUTLINING EVALUATIVE RESULTS FOR RESETTING GOALS, AND SELECTION OF RESEARCHERS WITH A WIDE RANGE OF INTEREST IN THE PROGRAM CONTENTS OR EASE IN DEVELOPING A WORKING KNOWLEDGE OF AND IDENTIFICATION WITH THE PROGRAM MISSION. RATERS OR USERS OF THE MEASURING DEVICE SHOULD BECOME AS FAMILIAR AS POSSIBLE WITH THE INSTRUMENTS. (DAG)