In the next decade, we hope that the targeting of ARID1A mutation by synthetic lethality will extend beyond the realms of academic interest and laboratory studies and show demonstrable benefit in clinical trials, and that clinicians at the bedside will be able to use ARID1A as a biomarker to triage patients that may potentially benefit from these novel therapies, offering a chance of improving survival in cancers with otherwise often dismal outlooks. The gene discussed is ARID1A; the disease is cancer.