Introduction: Biochemical recurrence (BCR) is a major clinical challenge in patients with Prostate Cancer (PCa), as rising PSA occurs in about 20-30% of patients treated with radical prostatectomy and up to 60% in patients treated primarily with radiotherapy. Patients may have local recurrence in the pelvis or in distant sites. The location and burden of recurrent disease is mandatory in guiding subsequent therapies. Standard practice for BCR in PCa includes computed tomography and bone scintigraphy, both known for limited diagnostic performance. The use of positron emission tomography (PET) with prostate-specific membrane antigen (PSMA) was introduced in clinical practice in the past few years due to its better accuracy. The present phase 3, prospective, multicentric, international study was planned to evaluate the diagnostic performance and clinical impact of [68Ga]Ga-PSMA-11 PET/CT in evaluating patients with biochemical recurrent PCa; the study was promoted and supported by the IAEA. Methods: Patients with PCa who have undergone primary definitive treatment and presented with rising PSA levels were recruited to the study. Overall 17 centers from 15 countries (Azerbaijan, Brazil, Colombia, India, Israel, Italy, Jordan, Lebanon, Malaysia, Mexico, Pakistan, Poland, South Africa, Turkey, and Uruguay) were involved. Images and data were centrally reviewed; data were collected and assessed for site of findings ([68Ga]Ga-PSMA-11 pathologic uptake), positivity rate (percentage of patients with a positive [68Ga]Ga-PSMA-11 PET/CT) and impact on patient management. Regarding PET findings, a composite reference standard was used, including pathology, correlative imaging, PSA response; regarding management, the reference included changes in the treating physician’s documented clinical plans before and after PET; all patients have at least 6 months clinical follow-up. Results: 1198 patients were prospectively enrolled between November 2017 and December 2019; 1004 patients had complete data for final evaluation. [68Ga]Ga-PSMA-11 PET/CT was positive in 654/1004 patients (65.1%); lesions were identified as: prostate/prostatic bed only in 13.7% of the cases; pelvic lymph nodes only in 20.5%, and with any metastatic disease in 27.0%. There was a correlation between [68Ga]Ga-PSMA-11 PET/CT positivity and Gleason score (p