Approved for public release, distribution is unlimited / The purpose of this thesis is to answer the question of how effective are current theater engagement / security cooperation plans at supporting US national interests. The examination of effectiveness focused on two theaters as case studies during the years 1998 through September 2001. This examination divided effectiveness down into two parts. The first part was consistency. Consistency was investigated by a comparison of the national priorities to completed engagement activities. The second part of effectiveness attempted to measure gains produced through the executed engagement missions. Following the case study analysis, key principles for effectiveness are identified and a modified engagement planning process proposed. The key elements of the modified process are integrated interagency planning, objective based engagement activities, and synchronization of all the elements of statecraft. This framework is tested by applying the modified TEP process to a sub-region of Africa. The significance for this test is not only to demonstrate the capability of the proposed TEP process. This test demonstrates the potential for effective engagement to assist in prosecuting the Global War on Terrorism (GWOT). In conclusion, this thesis provides an understanding of what engagement is today, and what engagement should be in the future. / Major, United States Army