Gunnar has a broad expertise within environmental and development economics. His research interests focus on environmental resources, development economics and in particular the interface between the two.

Methodologically he has a focus on non-market valuation techniques, household production models and broad reviews of existing literature. The applications have been focusing on evaluation of forest interventions in India and Ethiopia. This interest led to a series of papers on domestic energy demand, particularly focusing on India. Currently, his research is focusing on sustainable natural resource management in Africa, particularly adoption of soil conservation and the impacts on productivity in Ethiopia.