With his theory of communicative rationality, Jürgen Habermas has been one of the most influential social philosophers of the 20th century and a major dialogue partner for theology in the different stages of his work. Systematic and practical theology, theory of religious education and theological ethics have offered creative receptions and astute critiques. The book explores Habermas's renewal of Critical Theory of the first generation of the Frankfurt School through his paradigm change from the philosophy of consciousness to language. His postmetaphysical understanding of philosophy and the foundations of his discourse ethics are followed up into his recent demand for a species ethics in critique of genetic enhancement. The philosophical critiques of his work that are relevant for theology are explained and the successive phases of his view of religion are traced: supersessionism, co-existence, and finally cooperation in offering specific resources and shared criteria for public debate on the future directions of a technologically shaped pluralist culture.