This publication presents an overview of a series of "Hard Talks" held in Azerbaijan, Bosnia and Herzegovina, Georgia, Kazakhstan, Serbia and Ukraine in 2016-2019, organized by UNECE. They promoted demand-driven debates held in each country on what is needed to change for the private sector to invest in sustainable energy and substantially increase the uptake of renewable energy. Information and data included in this report are extracted from the activities, which aimed to investigate barriers that hinder the full unfolding of renewable energy potential, and facilitated an open exchange between political decision makers, governmental officials, project developers, investors and technology providers understand the objectives and actions of other countries. The project aims to contribute concretely to climate change mitigation and sustainable development