The COOL (=Climate OptiOns for the Long term) project has a twofold objective:- Developing strategic notions how drastic reductions of GHG emissions in the Netherlands can be achieved in the long term, in an European and global context, using a method of participatory integrated assessment.- Making recommendations for improving the methodology of participatory integrated assessment, in particular regarding (1) stakeholder participation, (2) utilisation of knowledge by stakeholder participants, and (3) facilitating the linking of the three geographic and political levels (NL, EU, global) by stakeholders.This report focuses on the second objective of the COOL project. The COOL project consists of three subprojects: a national, an European and a Global dialogue. The three projects have starting points in common, but have developed throughout their running in partly different directions. All three projects are evaluated with respect to their dialogue structure, the utilisation of knowledge by participants in the participatory integrated assessment and with respect to the interactions between the three projects. From these evaluations lessons are drawn how in the future participatory integrated assessment projects can be better organised and how they can better contribute to - in this case - climate change policy making.