G-protein-coupled receptors are an important class of therapeutic drug targets by virtue of their roles in the regulation of diverse cellular functions. Recent advances in the expression of heterologous G-protein-coupled receptors in the yeast Saccharomyces cerevisiae have led to the development of sensitive and selective assays of their ligand-induced activation. Implementation of this new technology in the high-throughput screening of compound libraries has enabled the discovery of novel ligands for the G-protein-coupled somatostatin receptor. This article describes the broad applicability of the technology and its use in drug discovery.