In his article "The Missional Church" Tim Keller discusses the need for and the elements of a missional church . Here is an excerpt from his article:
The British missionary Lesslie Newbigin went to India around 1950. There he was involved with a church living 'in mission' in a very non-Christian culture. When he returned to England some 30 years later, he discovered that now the Western church too existed in a non-Christian society, but it had not adapted to its new situation. Though public institutions and popular culture of Europe and North America no longer 'Christianized' people, the church still ran its ministries assuming that a stream of 'Christianized', traditional/moral people would simply show up in services. Some churches certainly did 'evangelism' as one ministry among many. But the church in the West had not become completely 'missional'--adapting and reformulating absolutely everything it did in worship, discipleship, community, and service--so as to be engaged with the non-Christian society around it. It had not developed a 'missiology of western culture' the way it had done so for other non-believing cultures... Most traditional evangelical churches still can only win people to Christ who are temperamentally traditional and conservative. But, as Wolff notes, this is a 'shrinking market.' And eventually evangelical churches ensconced in the declining, remaining enclaves of "Christendom" will have to learn how to become 'missional'. If it does not do that it will decline or die. We don't simply need evangelistic churches, but rather 'missional' churches.
The full article is available here.