Companies need to renew themselves to be able to compete in the dynamic global markets. Especially for the SMEs this is often challenging due to their weaker risk tolerance and fewer resources. Co-operation is often considered to be effective way to tackle these challenges and considerable amount of public funding has been directed to stimulate this co-operation. Still, deep research and development (R&D) co-operation between companies exists rarely. The paper presents qualitative analysis on co-operation in two joint R&D projects. The level of inter-firm co-creation in studied cases was low. This was explained by lack of resources, differences of R&D goals and changes in project consortium. Finally, we present two possible solutions to increase the level of inter-firm co-creation in joint R&D projects.