Specializing in forest management, policy and legislation, and forest stakeholder analysis, he advanced his career as a senior lecturer at UMS. He taught various subjects such as Forest Engineering, Forest Management, International and Regional Forestry, Forest Policy and Legislation, Forest and Wood Products Certification, Forest Valuation, Industrial Revolution and Research Methods, and Policy, Laws, & Regulations in the Timber Industry. He participated in various high-level courses internationally, such as Forest Genetic Resources in China (AFROGEN, 2023), Education for Improving Forest Governance in Southeast Asia, Laos (CIDT/DFID, 2016), International German Alumni Summer School, Nepal (DAAD, 2016), Management and efficient use of resources in the context of climate change, Vietnam (DAAD Alumni, 2017), and Working Effectively at the Interface of Forest Science and Forest Policy, Argentina (IUFRO, 2009). He is currently affiliated with multiple organisations, including the International Society for Development and Sustainability (ISDS), the Sabah Association of Social Forestry (SASOF), the Kadazan Dusun Cultural Association (KDCA), and the Malaysian Society of Agroforestry (MySAF). He has participated in various consultancies, such as developing the National Roadmap for Social Forestry in Malaysia (KeTSA, 2017-2020), WWF-Malaysia Community Engagement and Education (CEE) (WWF, 2017), serving as a Research Advisory Committee (RAC) Session Panel Member (FRIM, 2021), contributing to the development of Sabah Social Forestry Guidelines (KIPMAPS) (WWF Malaysia, 2023-current), and being a Member of the National Committee for preparing the Biodiversity Conference Resolution (KeTSA, 2023).

Dr. Walter Lintangah holds PhD (Sains Perhutanan) from Technical University Dresden, Germany , among other qualifications, and has established themselves as a respected expert in their field.