Pediatric surgical care in low- and middle-income countries is often hindered by systemic gaps in healthcare resources, infrastructure, training, and organization. This study aims to develop and validate the Global Assessment of Pediatric Surgery (GAPS) to appraise pediatric surgical capacity and discriminate between levels of care across diverse healthcare settings. The GAPS Version 1 was constructed through a synthesis of existing assessment tools and expert panel consultation. The resultant GAPS Version 2 underwent international pilot testing. Construct validation categorized institutions into providing basic or advanced surgical care. GAPS was further refined to Version 3 to include only questions with a > 75% response rate and those that significantly discriminated between basic or advanced surgical settings. GAPS Version 1 included 139 items, which, after expert panel feedback, was expanded to 168 items in Version 2. Pilot testing, in 65 institutions, yielded a high response rate. Of the 168 questions in GAPS Version 2, 64 significantly discriminated between basic and advanced surgical care. The refined GAPS Version 3 tool comprises 64 questions on: human resources (9), material resources (39), outcomes (3), accessibility (3), and education (10). The GAPS Version 3 tool presents a validated instrument for evaluating pediatric surgical capabilities in low-resource settings.