In 1997, the Chairman of the Joint Chiefs of Staff (CJCS) directed the five geographic combatant Commander in Chiefs (CINC) to formally link their regional operational engagement objectives with the national strategic objectives by developing theater engagement plans (TEP). The intent of TEP is to act as a deterrence by strengthening allied and friendly nations against external and internal threat, reduce causes of internal and external instability, assist in the development of host nation institutions that foster legitimacy, and encourage support to U.S. policies. Although TEP has been in existence for almost four years, TEP is still evolving both in the sense of a planning process and product. Currently there are no formal TEP joint terms or acronyms in joint publications because the joint staff is still developing TEP both conceptually and administratively. This monograph explores the ongoing evolution of TEP and the apparent paucity of information relating to TEP to determine if there is sufficient information available to develop TEP. Three criteria are used to answer the monograph question: sufficiency of national policy, doctrine and country and regional information. These criteria provide a lens through which to examine information requirements versus sufficiency to developing TEP. Because a planner develops operational engagement activities as part of TEP for individual countries, the monograph analyzes the sufficiency of information for developing TEP using Taiwan as a case study. The monograph has four chapters. The first chapter defines the problem with information relating to TEP and examines sufficiency of national policy and doctrine relating to TEP. Chapters two and three examine criteria for evaluating a country and determine their relevance and sufficiency of information for TEP. The monograph concludes by analyzing information requirements versus information sufficiency and identifies implications for developing TEP and for the PACOM staff charged with developing TEP for Taiwan.