(PLEASE KEEP IN WORD, DO NOT PDF) Enter the text here that is the new abstract information for your application. This section must be no longer than 30 lines of text. Interstitial cystitis/bladder pain syndrome (IC/BPS) and chronic prostatitis/chronic pelvic pain syndrome (CP/ CPPS), are common, costly, and debilitating syndromes characterized by persistent bladder and/or pelvic pain, and urinary symptoms, such as urgency and frequency. The cause of these conditions, together referred to as urologic chronic pelvic pain syndrome (UCPPS), is unknown and their pathophysiology is poorly understood,making treatment challenging. Although several therapies have been proposed for UCPPS, none has been found to work consistently in all patients and each is either invasive or prone to significant side effects. Therefore, new therapeutic approaches are clearly needed. One such promising, but understudied, approach is dietary exclusion. This approach is supported by findings from one small single-arm trial (n=10), two case reports, our recent Multidisciplinary Approach to the Study of Chronic Pelvic Pain 1 (MAPP-1) Research Network case-crossover study, and several patient surveys indicating that a large proportion of patients believe that diet triggers their flares. However, as patient-reported triggers are numerous and wide-ranging (up to 144 candidates), identification of one common diet suitable for all patients has proven challenging. Elimination diets are also difficult to implement and test because of the large number of possible food triggers that need to be eliminated in the “elimination” phase, the large number that need to be re-introduced in the “re-introduction” phase, and the challenges of blinding elimination diets. Therefore, tools to personalize these diets are urgently needed. In pilot trials of patients with migraines, Crohn’s disease, irritable bowel syndrome, and asthma, researchers have observed significant symptom reductions following exclusion diets informed by food-specific IgG antibody concentrations. This approach is promising because it reduces the time, complexity, and burden of dietary exclusion, while simultaneously increasing its chance of success and potential for rigorous blinded evaluation. Food-specific IgG antibodies are also plausible candidates to inform UCPPS therapy because they act by biologic mechanisms implicated in UCPPS pathology (e.g. mast cell degranulation and histamine release) and in a “delayed” time frame (hours to days) consistent with patient-reported food trigger experiences. However, before we can initiate a randomized controlled trial (RCT) of food-specific IgG antibody-informed exclusion diets for UCPPS, additional empirical evidence is necessary to support this approach. For many conditions for which biomarker-informed exclusion diets have shown preliminary efficacy, researchers first demonstrated a greater likelihood of having food-specific IgG antibodies in patients than controls. We have also gener...