In the time and spirit of the Second Vatican Council, in 1965 a joint working group between the Roman Catholic Church and the World Council of Churches was inaugurated. It has served as a catalyst to fruitful collaborations between the two bodies, supported the ecumenical endeavours of each other, and launched special projects of its own. Now, almost 50 years on, the Joint Working Group reports on its latest work. Its report is a window on the deepening relationship and evolving understanding of ecumenical bonds. Also included in the report are three vital studies, offering insights into the process of reception of ecumenical agreements, the spiritual roots of ecumenical engagement, and the complex yet promising relationship of the church and youth.