Cardinal Kasper is a fine theologian who was a colleague of Cardinal Ratzinger and Hans Kung at The University of Tubingen. Kasper now heads the Vatican's Council for Christian Unity. He has the specific task of trying to heal the rift between The Roman Catholic Church and The Russian Orthodox Patriarchate in Moscow, among other things.

By any reckoning, Kasper is a key player in the Christian Churches today. In this new book, his first to appear in English since Jesus the Christ (Burns & Oates) he outlines his vision for the unity of Christian Churches. Although Kasper has one of the top jobs in The Roman Catholic Church today, he is a man with an open mind.

The interpretation in this book of the uniqueness of The Catholic Church and its Magisterium is nonetheless progressive as he understands that truth is something that no-one has a monopoly on. The Catholic Church must listen to other traditions and learn from them. But Kasper also realizes that the cause of unity is exceptionally difficult at the present time.

The lack of central teaching authority in the Anglican Communion is extremely problematic. The politics of the relationship between Rome and Moscow have seldom been more fraught. This book will command quite exceptional interest. Many will read it in the hope that this highly intelligent, open-minded Church leader may give hope to people of all traditions that they may learn to understand Jesus's injunction - 'they may be one'.