For over twenty years, Evangelist Daniel King has conducted large evangelistic events in nations around the world. In this ground breaking academic study, he examines the history, the theology, and the effectiveness of mass evangelism. His research is valuable for anyone who is studying evangelism or who is called by God to be an evangelist. This is an Applied Research Project submitted to the theological faculty of Oral Roberts University in partial fulfillment of the requirements for the degree of Doctor of Ministry. The goal of this study was to use surveys of an evangelistic event in Caic, Brazil to examine these important questions: * Are mass evangelistic campaigns effective? * Who comes to an evangelistic campaign? * Are local churches involved? * How are attendees impacted by the event? * Are people really being saved and healed? * Is follow-up effective? * How can the methods of evangelists be improved?.