Recent European policy highlights the need to promote local fishery and aquaculture by means of innovation and joint participation in fishery management as one of the keys to achieve the sustainability of our seas. However, the implicit assumptions held by the actors in the two main groups involved – innovators (scientists, businessmen and administration managers) and local fishermen – can complicate, perhaps even render impossible, mutual understanding and co-operation. A qualitative analysis of interviews with members of both groups in the Valencian Community (Spain) reveals those latent assumptions and their impact on the respective practices. The analysis shows that the innovation narrative in which one group is based and the inventions narrative used by the other one are rooted in two dramatically different, or even antagonistic, collective worldviews. Any environmental policy that implies these groups should take into account these strong discords.