Wikipedia
In Christianity, postdenominationalism is the attitude that the Body of Christ extends to born again Christians in other denominations (including those who are Non-denominational ), and is not limited just to one's own religious group. Its focus on doctrine distinguishes it from Ecumenism.
Many of the fastest growing Evangelical churches in the world do not belong to any "established" denomination, though the tendency is that over time the larger ones form their own organization (though they will not call it a "denomination"). The world's largest postdenominational organization by membership and number of congregations is the Covenant Christian Coalition.
According to David Barrett,, in addition to this, there are 60 million Americans who are born again believers, and do not attend any church. Though this is often due to faults in the church (some cite visionless leadership, unresolved sin issues amongst church bodies, lax morals in the pews, money mishandling, etc. in their reasons for not attending), postdenominationalists nevertheless consider that the Church is at the center of God's plan for the world.