This Special Issue comprises original research contributions on the changing landscape of sustainability policies and their economic and social impacts. The first paper duscusses the 'green growth' and 'de-growth' recipes for global climate change. The other ten papers address the transition policies of two major actors of the world system: the European Union (five papers) and China (five papers). The papers show that, in spite of the huge differences between the EU27 and China, in both cases, environmental and climate energy policies, as well as circular economy policies, can be effective in driving the sustainability transition or some of its core processes. Effectiveness emerges for a broad range of different policy approaches. A clear-cut conclusion emerging from the papers is that innovation, technological, social or institutional, is the key lever to make policies effective.