Rangsan has over twenty years of experience in the area of corporate finance and strategy. He began in New York before returning to his native Thailand. Notable previous experience includes taking part in financing Thailand's first private infrastructure toll-road, Donmuang Tollway, structuring and managing a state enterprise provident fund, Thai Airways International, underwriting the foreign tranch of a listed power producer and raising funds to invest in the country's first mass transit train system, Bangkok Mass Transit System. Prior to founding Prudent, Rangsan key positions were n the investment banking circle including Vice President for Thai Investment and Securities Company Plc. (TISCO, a subsidiary of the former Bankers Trust), Head of Peregrine's Investment Banking in Thailand.
At Prudent Advisory, Rangsan has successfully turn around several companies both public and private using his skills in corporate finance and strategy. Rangsan is also on Executive Committee for the Bangkok Symphony Orchestra, visiting lecturer to local seminars and business schools and was a Honorary Advisor to the Committee on Finance, Banking and Financial Institutions for the House of Representatives. Rangsan is also a Charter Member of the Society for Advancement of Consulting, USA, a practitioner of the Adizes Methodology.