Since the beginning of the Global War on Terror (GWOT) in 2001, the premium placed on Special Operations Forces (SOF) by political and military leaders has increased exponentially. With each passing year, the demand for SOF units surpasses supply, even as both the U.S. Special Operations Command and the Joint Special Operations Command expand rapidly in size and budget.

For example, the 75th Ranger Regiment added an additional line company to each of its three battalions—there are now four companies to each battalion. Both Delta Force and SEAL Team 6 added an extra assault squadron.

The Naval Health Research Center (NHRC) conducted a study titled “Predictors of Success in Basic Underwater Demolition/SEAL (BUD/S) Training: What Do We Know and Where Do We Go From Here?” Divided into two parts, the research had a dual purpose:

1) “Review the currently available literature addressing factors and characteristics that may predict the performance and success of Basic Underwater Demolition/SEAL (BUD/S) candidates.”