Morbid obesity is a rapidly escalating problem in the United States, one with serious health ramifications. Due to the lack of empirical support for the long-term efficacy of non-surgical interventions for obesity, gastric bypass surgery has been pursued with increasing frequency as a treatment for morbid obesity. Because surgery is a high-risk, invasive treatment option, medical, psychological and behavioral factors must be carefully considered in pre-surgical evaluations. Although psychological evaluations are requested by surgical teams, there is currently no commonly used, standardized protocol for this type of assessment. Further, there is little empirical data specifying which factors predict successful surgical outcomes. A general overview of a semi-structured interview for pre-surgical gastric bypass evaluation, developed by the Medical Psychology Service at the VA Boston Healthcare System, is provided in this paper. This standardized approach has many advantages: it ensures comprehensive assessment of relevant factors; it facilitates both research and training; and it facilitates patient education about the procedure.