Genetic variation may account for variations in drug responses that are unaccounted for by conventional efforts to optimise drug response. The use of pharmacogenomics (PGx) may optimise pharmacotherapy in terms of safety and efficacy and provide individualised therapeutic choices. There is established evidence and guidelines for multiple drug-gene pairs to support the clinical implementation of PGx and some examples that are pertinent to primary care are briefly described. This article also outlines the landscape of the use of PGx in Singapore and addresses the potential concerns about insurability and genetic counselling for PGx tests.