Recently a friend asked for a simple, not-too-academic, listing of some primary books on ecumenism that I have found helpful. My answer is below. Forgive me for putting my own books at the top of this list but I do believe they are important for serious interest in this discussion and my name just happened to come first alphabetically. When I was in school I hated being called on first but sometimes it has had its advantages.
I have put an asterisk by the seven books that I recommend most if you are interested in a shorter reading list. By far the Rex Koivisto volume is the best evangelical work on the subject.
Bibliography of Ecumenism
*Armstrong, John H.; Your Church Is Too Small: Why Unity in Christ’s Mission is Vital to the Future of the Church (2010)
*Armstrong, John H.; The Unity Factor: One Lord, One Church, One Mission (2011).
Boardman, George Dana; The Church: The Divine Ideal (reprint, 2008)
*Braaten, Carl E. and Robert W. Jenson; The Catholicity of the Reformation (1996)
Braaten, Carl E.; Mother Church (1998)
Bromiley, G.W. ; The Unity & Diversity of the Church (1958)
German National Bishops’ Conference and Daniel R. Smith; Communio Sanctorium: Official German Catholic-Lutheran Dialogue (1999)
Fournier, Keith; A House United? (1994)
George, Timothy and John Woodbridge; The Mark of Jesus (2005)
*Harmon, Stephen R.; Ecumenism Means You, Too: Ordinary Christians and the Quest for Christian Unity (2010)
*Kasper, Walter; That They All May Be One: The Call to Unity Today (2004)
Kasper, Walter; Searching for Christian Unity (2007)
Kasper, Walter; A Handbook of Spiritual Ecumenism (2007)
*Koivisto, Rex; One Lord, One Faith (reprint/revised, 2010)
Lowery, Mark; Ecumenism: Striving for Unity Amidst Diversity (1985)
Meyer, Harding; That All May Be One: Perceptions and Models of Ecumenicity (1999)
Schreiter, Robert J.; The New Catholicity (1997)
Seitz, Christopher R.; Nicene Christianity: The Future for a New Ecumenism (2004)
*Van Beek, Huibert; Revisioning Christian Unity (reprint, 2009)