This perspective report will focus on the ethical, legal and social issues raised by pharmacogenomic research using large population-based databases. Access to databases established or developed at the level of whole populations or communities (e.g., the Estonian Genome Project, the UK Biobank, CARTaGENE, GenomEUtwin, and so on) will become increasingly important in pharmacogenomic research for the purpose of confirming associations between genetic variations and drug-related effects. The capacity of database creators and managers, along with that of researchers, to meet the ethical issues raised by such vast public projects will determine the integration of pharmacogenomics into mainstream clinical practice.