There is a steady increase in knowledge about environmental challenges and solutions, as well as about how solutions within different environmental fields may affect each other. The organization of these various types of streams of knowledge is, however, increasingly segregated by the need for effective and specialized management. Thus, while the challenges are integrated, organizational responses tend to be fragmented. Also, domestic management systems rely heavily on domestic research institutions. Domestic decision-makers are therefore increasingly exposed to complex scientific findings produced at different levels of governance by a variety of knowledge producers in different issue areas. We look into how knowledge from various sources is dealt with and organised within four environmental issue areas in Norway: management of protected forest areas, freshwater management, persistent organic pollutants (POPs) and nanotechnology.