During the week of 17 to 21 July, UNDESA and IAEA, conducted a workshop and data gathering mission to Accra to start the implementation of a CLEWs capacity development project in Ghana. The mission and workshop are part of the joint initiative of UNDESA and UNDP to promote in-depth capacity development on modelling tools to inform sustainable development policies. The policy relevance and main methodological features of the CLEWs integrated assessment modelling tool were presented along with the preliminary results developed by three government officials trained in the CLEWs Trieste Summer School organized in 12–30 June 2017. The presentation of preliminary results by the government team significantly increased the interest of the government institutions participating in the workshop as it clearly demonstrated the relevance and utility of the tool. The mission was successful in defining the data requirements, strategy of engagement of modelling teams in national institutions, and refining the policy objectives of the project.