Which actors are involved, which role can they play, and how is responsibility shared between different actors?

Several different types of actors are involved, e.g. governments, businesses, educational institutions, and individual consumers. Which others are relevant? How can each of these actors contribute to transformational change? For example, consumers can change their behaviour, such as their diets. What else can they do? What can others do? What of the different actions for each actor is most effective?

We can also think of actors as different countries. We cannot give the full responsibility solely to producers (especially developing countries) or to consumers (especially developed countries). It should be shared. But how, based on which criteria? Does the development stage and historical environmental degradation also play a role?