Abstract The present paper was written to show the implementation and evaluation of a HSE's leadership case study at Mansarovar Energy Colombia Ltd (hereinafter MECL). MECL is a joint venture of two state companies, SINOPEC from China and ONGC from India. HSE programs are designed to cause a transformation process that leads to enhance employee's life skills as part of the HSE area and their workforce readiness. The process should also impact the effectiveness and engagement of the HSE staff. MECL believes that company values and improvements on the professionals' behaviours can be effectively developed through the combination of academic programs and activities. A lack of cooperation between the HSE's areas reduces the know-how accumulation and sharing and results in a failure to achieve individual, area, and/or corporate goals, as is stated on the balanced scorecard. For this case study, the HSE leadership program was based on the integration of the principles in effective leadership, into various aspects of day to day company practices, especially for the professionals that work at the oil field. The implementation process was facilitated by the following pillars: The training and professional development of all HSE staff in leadership principles.The integration of leadership concepts by HSE professionals into HSE meetings, the provision of HSE training material, HSE 24/7 conversations, and a wide range of activities developed with the purpose of fostering the understanding, deployment, and application of these principles into the workers.The maintenance of project's goals, through coaching and group work sessionsThe evaluation of program effectiveness via HR (human resources) and HSE indicators. The HSE leadership program has led to a world class HSE's culture at MECL. Indicators such as TRIR (Total Recordable Injury Rate), LTIF (Lost Time Injury Frequency) and Severity have remained below the values reported by OGPi for 2013. In addition, Vehicle Index Frequency (VIF) and spill events stay under control with low values. The results of "Great Place to Work Survey" have increased from 61.5 to 72.4 out of 100 points for the period 2012-2014, which indicates an improved synergy, leadership and alignment with common goals at MECL.