Purpose: The purpose of this study was to identify what Colombians perceive as effective and least effective/ineffective managerial behavior. Design/methodology/approach: This study was conducted following a qualitative methodology based on the philosophical assumptions of pragmatism and the "pragmatic approach" (Morgan, 2007). The critical incident technique was used to generate data from a purposive sample of 27 managers and non-managerial employees located in Medellin and Bogota, Colombia. Findings: The results of this study suggest that effective managers in Colombia are those who are supportive, caring, considerate, participative, understanding, communicative and flexible, and are also good problem solvers. Research limitations/implications: This study focused on the perceptions of Colombian managers and non-managerial employees only. Therefore, the description of effective and least effective/ineffective managers in Colombia could be highly value-laden from the national cultural perspective. Hence, it is recommended that further research should be carried out to explore the perceptions of international managers who have frequently interacted or worked with Colombian managers. Originality/value: The results of this study have practical implications for Colombian managers and international managers who manage the Colombian workforce. For Colombian managers, this study provides insight into what is considered effective or least effective/ineffective managerial and leadership behavior. The findings provide useful information on foreign multinational corporations (MNCs) that have operations in Colombia. MNCs can use the results of this study to create effective management development models for their expatriates in Colombia.