Rev. Brendan Leahy, professor of theology at St. Patrick's College in Maynooth, Ireland, talks about his new book, Ecclesial Movements and Communities, which traces the origins and significance of movements such as L'Arche, Focalare, Communion and Liberation and the Community of Sant'Egidio. Fr. Leahy discusses the unique charisms of these communities and the ways in which they were shaped by the Second Vatican Council. He also explains how they serve as an important form of church life for both priests and lay people at a time when vocations are dwindling and parishes attendance is in decline.