 If he were to choose just one key element in those years it would be the fresh, multifaceted involvement in ecclesiology that this has remained at the forefront of his thinking ever since.He recrossed the Atlantic to be Director of the Princeton Center of Theological Inquiry for five years.Much of his time there was spent in rethinking the Center (along lines now happily being pursued by the current Director) and in working closely with individual members from many disciplines and many countries.