Olefin metathesis is a powerful transformation based on catalytic reaction between alkenes. It allows a formation of a variety of structurally diverse molecules that cannot be easily prepared by alternative routes. Recently developed methods require relatively low catalyst loading and enable easy removal of residual ruthenium from the reaction product. These developments have attracted the attention of process chemists who add metathesis reaction to a toolbox of reliable methods for production of pharmaceuticals. This review presents selected examples of successful application of olefin metathesis in the synthesis of active pharmaceutical ingredients from laboratories within the pharmaceutical industry.