The objective of this study is to explore key success factors in each development phase of Hyundai Oilbank\'s action learning programs for organizational development(OD) by using a longitudinal case study. A research model for longitudinal case study was established based on the results of previous studies that were conducted to identify key success factors of action learning programs for OD from the perspective of PLC(product life cycle) theory and cross-sectional analysis. This model, then served as a basis for analyzing internal documents and conducting in-depth interviews with internal experts. Based on the results drawn from this research activity, the action learning programs that Hyundai Oilbank has executed since 2002 were divided into 3 development phases: establishment(2002-2003), quantity enhancement(2004-2006), and quality maturity(2007-present). Furthermore various policies, events, systems, and programs were analyzed to explore key success factors of each phase. Out of 11 key success factors that were identified during cross-sectional analysis, the results suggested that there are 5 factors in the establishment phase, 10 factors in the quantity enhancement phase, and 11 factors in the quality maturity phase. To conclude this study, theoretical and practical implications and limitations of this study were examined and agendas for future research were proposed.
Key words : Action Learning, Organization Development, Human Resource Development.