Background: Research priorities in germ cell tumor (GCT) management have moved sharply from therapeutic improvements to cancer care delivery research and biomarker-based decision making. Early intervention with centralized decision support and oversight by expert teams result in best therapeutic outcomes and survivorship with decreased resource utilization. We describe Kaiser Permanente Northern California’s (KPNC) re-organization of care delivery through rapid case ascertainment and early expert input, as well as early results of reduction in practice variation and system-wide practice change. Methods: In 2016, KPNC reorganized oncology from a distributed generalist model to a model led by a centralized multidisciplinary expert team to share in initial and ongoing care delivery for all GCT patients in the system. Central to the re-organization was rapid ascertainment of the entire population of patients with GCT within the system and early expert engagement in treatment decision-making. Results: Between May 2016 and June 2018, 274 GCT patients were recorded in the tumor registry, of whom 69% were < 40 years of age, 16% were non-white, 56% had seminoma and 63% had stage 1 disease. Rapid case ascertainment identified 89% (95% CI, 86-93%) of the cases, increasing from 79% in 2016 to 97% in 2018 as false negatives were identified and used to improve the case finding algorithm. The overall positive predictive value was 57% (52-62%) and number needed to detect was 1.75 (1.62-1.91). Of the 274 cases, 92% (89-95%) were engaged by the expert team. In addition, the team reviewed 61 testicular cancer patients who had recurrences or metastatic cancers. Among 177 patients with stage I seminoma, the preferred use of active surveillance over adjuvant chemotherapy or radiation therapy rose from 48% (95% CI, 35-62%) in 2015 to 87% (75-99%) in 2018 (p = 0.0005). For patients with nonseminoma, the rate of the preferred option of retroperitoneal lymphadenectomies being performed by a high volume urologic surgeon increased markedly from 62% in 2015 to 95% in 2018. Conclusions: To our knowledge, the KPNC re-organization of GCT care delivery with comprehensive rapid case ascertainment is unique for integrated health care delivery systems in the USA. While early, KPNC has a working platform for early, expert multidisciplinary review and bidirectional communication with local care teams for population-based care. Early evidence points to system-wide reductions in practice variation and improvements in practice.