This contribution undertakes a critical assessment of the well-known Hans Küng's proposal for contemporary ethics in his book Global responsibility. In search of a new world ethic (1990). This article commences by providing some background on this publication as well as on the theology of Küng in general. The content of the book is then paraphrased in summarised form. The last part of the article analyses four major convictions of Kung, against which the Reformed doctrine is brought forward. These convictions deal with the ethical aspects of normativity, humanity, postmodernity and ecumenicity.