Pawana Thammasila has vast experience with regard to the inspection of large businesses and multinational corporations as she was responsible for supervising the large tax payer offices (around 2,500 offices) while she was the Director of Large Business Tax Administration following 36 years of service in the Revenue Department.

She also launched the service excellence tax office project, which she instigated in eight provinces of the lower Northern provinces of Thailand while she was working for Revenue Office 7. In 2011, she received the United Nations Public Service Award, which is a prestigious award in the advancement of knowledge management in government.