Increased interaction between science and society is recognised as one of the characteristics of contemporary science. Solving the complex environmental problems of our day also necessitate such interactions. In this thesis, theories of knowledge production and innovation, including the triple helix and Mode 2, were used to analyse and assess environmental science critically. The triple helix model claims that interaction between university, industry, and government, is essential for innovation development. The Mode 2 of science emphasises the social embeddedness of science. These theories of knowledge production are situated on a macro level. Most studies carried out about this have disregarded the interactions in practice between science and society. The aim of the thesis was to explore how these theories manifest themselves in practice. Further, the aim was to contribute to knowledge about cross-sector interactions in environmental research collaboration. Interactive research was conducted in three environmental research projects. One survey was also conducted on a national level. Results are distributed in five research papers. Firstly, the results showed that the triple helix became somethings else on a project level. Further, when working in a triple helix-based collaboration participants encountered boundaries and which could be crossed using boundary-spanning means. The use of dialogue arenas in interactive research, meaning research oriented workshops and seminars, aided both participants and the researcher to cross disciplinary and cross-sector boundaries. Solving environmental problems, using cross-sector research collaboration, necessitated the recognition of the collaborative process itself. An abstract environmental idea such as the circular economy was also found to contribute to bridging the gaps between research and society. Lastly, the research showed that environmental scientists reflect upon the relevance of their research. The scientists felt the need to provide society with relevant research and adjust their research choices due to this. This thesis ends up with a discussion about a Mode 3 of knowledge production where the democratisation of research is crucial. Here a fourth helix represents the further inclusion of society in general. A fifth helix includes the natural environment as a driver for collaboration, forming a quintuple helix which incorporates the environmental relevance into collaboration. This thesis contributes to knowledge about theories of knowledge production, cross-sector research collaboration and the role of environmental science in society.