With the rapid advances in high throughput genomewide technologies, enormous progress has been made in discovering genetic variants that inform therapeutic and adverse drug response. In addition, novel study designs such as the reverse genomewide association study, or the phenome-wide associations study, PheWAS, are being used to make further discoveries in personalized medicines. Increasingly, these discoveries are being translated into medical practice as genetic data are being used to guide the selection of drugs and doses. The focus of this collaborative symposium jointly sponsored by the British Pharmacological Society and the American Society for Clinical Pharmacology and Therapeutics, will be on the use of novel and high throughput genome wide approaches for discovering genetic biomarkers that inform drug therapy including safety biomarkers. Incorporation of genome wide data in the electronic medical record to facilitate drug dosing and selection will be described along with the challenges in the use of genetic information in clinical patient care.