This research is a research and development study, aiming at examining the gaps between current & expected situations, exploring common insights on Leadership development, and proposing a Leadership development model. The research site is in Thailand, involving six private-higher education institutions/universities. The participants in this study consisted of full-time faculty members and staff, totaling 101 people, and full-time Deans, totaling 25 people. Research instruments included a needs assessment questionnaire and an appreciative inquiry interview. Data treatments and validity included descriptive statistics; priority needs index, contents analysis, and field experts' reviews. The quantitative findings in term of the ranking indicated that human resource management was ranked the first-order need, followed by risk management which was ranked the second-order need, then brand management which was ranked the third-order need, then change management which was ranked the fourth-order need, and lastly, strategic management which was ranked the fifth-order need. The quantitative results implied that there was the gap in the experience of the fellows of the Deans who are faculty members and staff. The largest gap between the current and expected situation was in the area of human resource management and risk management. The overall quantitative results are congruent with the qualitative findings of the appreciative inquiry interviews with 25 Deans, revealing that three attributes that commonly contributed to the Leadership Development Model are: people development, organization culture management, and whole-systems management and development. These attributes are highly valued and commonly patterned as an integrative model of the practicing and enabling systems of the Leadership where each attribute interdependently bolsters one another.