Book excerpt: Effective evangelistic sermons require preachers to know their audience and to tailor their preaching accordingly. Chris Altrock uses findings of the Barna Research Group and his own experiences as a preacher to support his descriptions of several characteristics common to the unchurched or the lost crowd today. Recognizing that the audience today is vastly different from previous generations, Altrock suggests several approaches to these postmodern listeners, challenging preachers to change in order to reach the "field of harvest" that Jesus calls the church to love.