This overview of Habermas' work explores the way in which his theories have developed and changed, leading to an exposition of his more complex ideas and theories. His theory of communicative action is analysed, as are key themes, such as rights, public deliberation, law and democracy, and how they inter-relate. The question of how institutions can be designed to facilitate problem solving and conflict-resolution in a communicative manner is also discussed, and so is Habermas' contribution to the theory of international relations.