This article discusses the implications of the emergence and growth of the non-denominational church and the concurrent development of megachurches in mainline denominations. Is there a future for the mainline church? Why has it declined in the last fifty years while non-denominational churches have grown? Does this decline signal a new move by God and a need to redefine how we do church? The answer is found both in a theological understanding of the church and in an examinination of the cultural and technological developments of the last half of the twentieth century.Ecclesiology is a branch of systematic theology that seeks to reflect on the purpose, nature, and ministry of the church. The term ekklesia embraces Christianity as a religion and the church as an institution. An ecclesiology should include an understanding of how the Eucharist, baptism, preaching, and institutional life make up a definition of the church. The dialogue between orthodox understandings of ekklesia and liberation theologies has expanded the understanding of the task of the church to include social and political issues as well as orthodox claims of spirituality and traditional teachings. Orthopraxis has become a common term used by liberation theology in this dialogue. The word "church" can designate either local assemblies of Christians or the universal Christian community. 1 Here we understand the term to embrace God's desire institutionally to manifest his saving work in Jesus Christ in history through gathered fellowships of the faithful. A new ecclesiology continues the ongoing task of theology to interpret the