The objective of this study is to update evidence-based best practice guidelines for pediatric/adolescent weight loss surgery (WLS). We performed a systematic search of English-language literature on WLS and pediatric, adolescent, gastric bypass, laparoscopic gastric banding, and extreme obesity published between April 2004 and May 2007 in PubMed, MEDLINE, and the Cochrane Library. Keywords were used to narrow the search for a selective review of abstracts, retrieval of full articles, and grading of evidence according to systems used in established evidence-based models. In light of evidence on the natural history of obesity and on outcomes of WLS in adolescents, guidelines for surgical treatment of obesity in this age group need to be updated. We recommend modification of selection criteria to include adolescents with BMI >or= 35 and specific obesity-related comorbidities for which there is clear evidence of important short-term morbidity (i.e., type 2 diabetes, severe steatohepatitis, pseudotumor cerebri, and moderate-to-severe obstructive sleep apnea). In addition, WLS should be considered for adolescents with extreme obesity (BMI >or= 40) and other comorbidities associated with long-term risks. We identified >1,085 papers; 186 of the most relevant were reviewed in detail. Regular updates of evidence-based recommendations for best practices in pediatric/adolescent WLS are required to address advances in technology and the growing evidence base in pediatric WLS. Key considerations in patient safety include carefully designed criteria for patient selection, multidisciplinary evaluation, choice of appropriate procedure, thorough screening and management of comorbidities, optimization of long-term compliance, and age-appropriate fully informed consent.