In 1921, Brunner published his Habilitationsschrift (a post-doctoral dissertation traditionally required in many countries in order to attain the position of a fully tenured professor) on Experience, Knowledge and Faith and in 1922 was appointed a Privatdozent at the University of Zurich.

After accepting various invitations to deliver lectures across Europe and the United States, in 1930 Brunner published God and Man and in 1932 The Divine Imperative.

In the same year, he was a substantial contributor to the World Conference on Church, Community, and State in Oxford, a position which was reflected in his continued involvement in the ecumenical movement.

Before the outbreak of the war, Brunner returned to Europe with the young Scottish theologian Thomas F. Torrance who had studied under Karl Barth in Basel and who had been teaching at Auburn Theological Seminary, New York (and who would subsequently go on to distinguish himself as a professor at the University of Edinburgh).

Following the war, Brunner delivered the prestigious Gifford Lectures at the University of St Andrews, Scotland, in 1946–1947 on Christianity and Civilisation.

While returning to Europe from Japan, Brunner suffered a cerebral haemorrhage and was physically impaired, weakening his ability to work.

However, Brunner was a Protestant theologian from German-speaking Europe (a heritage which did not lay nearly as much weight on the Calvinist–Arminian controversy as Dutch- or English-speaking theology).