As genetic testing plays an increasingly salient role in the realm of cancer diagnosis, prognostication, and treatment, this review aims to elucidate the current landscape and future directions of genetic testing in genitourinary cancers, with a focus on prostate cancer, urothelial carcinoma, and renal cell carcinoma. With the increasing adoption of next-generation sequencing technology, the utilization and access to genetic testing in real-world settings have become critical for practicing urologists and genitourinary oncologists, especially after the approval of poly(ADP-ribose) polymerase inhibitors for prostate cancer and the utilization of immune checkpoint inhibitors. In this rapidly evolving field, this review underscores the clinical value of interpreting genetic variations and the importance of distinguishing between germline and somatic mutations, for whom testing can be prescribed, and which genes should be tested. While the current modus operandi predominantly relies on exome sequencing, we posit that the future of genetic testing in genitourinary cancers will see an expansion to encompass whole-genome sequencing, accounting for structural and regulatory variations that impact gene expression. In the upcoming era of liquid biopsies, we envisage an increase in noninvasive cancer genetic testing for the purposes of diagnosis, prognosis, treatment response, and progression monitoring, supplementing the gold-standard tissue biopsies that provide histologic information. Ultimately, thoroughly interpreting genetic testing results and the subsequent treatment implications necessitates a multidisciplinary approach. This review strives to offer urologists a comprehensive perspective on genetic testing in these prevalent urological cancers, contributing to improved diagnosis, prognosis, and treatment decision-making.