This article is an exercise in Practical Ecclesiology. The author reflects on church, mission and ethics from historical, hermeneutical and strategic perspectives. Using the ecclesiology of Karl Barth as a point of departure, the author argues that the church needs to be church if it wants to be a credible witness to the Gospel of Jesus Christ. Integrity is essential if a church wants to be missional. Integrity means the church has to become what it already is, the body of (...) Christ. This contribution is dedicated to Prof Graham Duncan, professor emeritus of church history, a man of integrity and dedicated to the missional calling of the church. (shrink)