Project CHECO has published several reports concerning Search and Rescue in Southeast Asia; however, no one definitive study has been made of the hundreds of Evasions and Escapes that have ended with the successful recovery of these downed crewmembers. Few subjects have proved to be as resistant to data-analytical examination as has Escape and Evasion, and for a multitude of reasons. Among them are the sensitivity of information regarding yet unrecovered crewmembers, lack of interface of information between the services, lack of retention of data over the many years of conflict, and%failure to establish a sole repository of such statistical data for all services. These present drawbacks will unquestionably be overcome through long term future study; for the present they are beyond the scope of this report. It is recognized that Intelligence has the primary role in Evasion and Escape, but this report will not attempt to detail the evolution of E & E related Intelligence activities during the period of this report. A subsequent report on USAF Support to Special Operations in SEA will fully treat the Intelligence role in E & E. What this study does intend to present is an empirical examination of the evolution of the techniques of evasion and escape from the early days of the conflict through the end of 1971. It shows the development of hardware - Life Support Equipment - and its increasing sophistication. The report will trace the growth of the Jungle Survival School at Clark Air Base, Philippines, and its gradual change in emphasis as more and more reports came back from recovered airmen in its continuing efforts to implant this knowledge in the minds of Southeast Asia-bound aircrew members. It will show the interface necessary between the Search and Rescue Task Force and the downed individual, along with necessity for the knowledge of how best to help them help him., Project CHECO was established in 1962 to document and analyze air Operations in Southeast Asia. Over the years the meaning of the acronym changed several times to reflect the escalation of operations: Current Historical Evaluation of Counterinsurgency Operations, Contemporary Historical Evaluation of Combat Operations and Contemporary Historical Examination of Current Operations. Project CHECO and other U. S. Air Force Historical study programs provided the Air Force with timely and lasting corporate insights into operational, conceptual and doctrinal lessons from the war in SEA.