Data from a series of four studies on leadership behavior are analyzed and compared to identify effective patterns of leadership behavior for platoon leaders and battalion commanders in ROK Army. Multiple-method research strategy is utilized in four studies to overcome some of the limitations of previous researches. Two of four studies employ a questionnaire method, and the rest use content analysis of critical incidents. Important behaviors for leadership effectiveness in both platoon leaders and battalion commanders include Supporting and Motivating Task Commitment. However, Developing and Monitoring Operations are only important in platoon level, and Planning & Organizing and Recognizing & Rewarding only in battalion level. Most discrepancies in results among studies can be explained in terms of either method effects or situational differences in role requirements for leaders.