Management of intracranial hypertension (ICH) in patients with severe traumatic brain injury (sTBI) is crucial to their survival and optimal recovery. The evidence-based Guidelines for the Management of Severe Traumatic Brain Injury, 3rd Edition recommends use of intracranial pressure (ICP) monitors to assess ICH and know when and how to intervene. Unfortunately in most areas of the world there is no access to ICP monitor technology. This means that most people with sTBI are treated without use of ICP monitoring. There are no Guidelines and no literature on how to treat sTBI without use of ICP monitors. The objective of this project is to create guidelines for the treatment of severe TBI in the absence of ICP monitoring and test them. The grant is about to enter its 5th year and requires a 6th and 7th year in order to be completed successfully ? specifically, with sufficient power to rigorously test the guidelines. We have developed a treatment protocol by working with a team of clinicians who practice in resource-limited environ- ments in low-to-middle income countries (LMICs) and routinely make decisions based either on an ad hoc treatment protocol, their clinical experience, or both. During grant year 04 we held a consensus conference attended by clinicians from 14 Latin American countries and developed a Consensus-Based protocol that is now being tested in 15 resource-poor centers, some of which have prior exposure to a less well developed ad hoc protocol for treatment of TBI, and others that have not had prior exposure. We are testing the influence of the protocol on outcomes of severe TBI in a before/after design in these two sets of centers. In Phase I, (now complete), patients were treated according to an ad hoc protocol developed in a prior RCT (the BEST TRIP Trial) or according to individual clinician best judgment. Following development of the consensus protocol, all sites were trained in its use, and have begun implementing study Phase II which will last through year 07. In each set of centers we are evaluating the effect of using the consensus-based protocol compared to either no protocol or the ad hoc protocol by comparing the outcomes in the first and second periods (Phase I and Phase II). Finally, we will evaluate how much more the consensus-based protocol effects outcome than the ad hoc protocol by comparing the difference from the first to the second period between the two sets of sites. If this newly developed protocol is effective for treatment of severe TBI, it could be used globally to improve outcomes for sTBI patients in situations where ICP monitoring is not available as well as in high income centers that choose not to monitor. The innovative approach of doing such research in LMICs allows us to work ?from the ground up? in developing sTBI treatment algorithms and testing the marginal benefits of added technology or techniques. Although of clear value to the LMIC settings where the research is done, such studies also provide unique and valuable scientific feedback to High Income Country centers where many of these new technologies have been widely adopted in advance of rigorous scientific support for their efficacy.