In an effort to counterbalance the inequalities and unequal power relationships that have resulted of globalisation; and to include varying perspectives of development in decision-making; non governmental organisations (NGOs) are increasingly acting as forums for marginalised and vulnerable communities. Through networks; NGOs have also enhanced the exchange of ideas; skills and knowledge between a wider sector of society. However; NGOs have been criticised by failing to effectively use their resources and capacities to significantly influence debates and decision making. To reach effectiveness; NGOs need to develop certain capacities and better understand their relationships. For this; planning and decision making support processes like strategic environmental assessment can be useful. In this paper the experiences that were gained by the museum members and communities of Samp Intercontinental Museum Network; a Swedish registered NGO; are presented. The results were participant engagement; process ownership; capacity mobilisation; and the identification of key issues to better understand the work of the network. It is argued that participative; adaptable and flexible strategic environmental assessment processes can support cultural network organisations to make their higher level guiding concepts operable; to share and develop capacities across borders and to reach long term transformations in society.