The key to chemical reactions is in the name—there needs to be something that causes the chemicals to react to one another. Called a catalyst, this component induces or speeds up reactions in a controlled manner to produce a desired outcome. The catalysts used in several industries are often composed of noble metals, which are not efficient enough to compensate for their high cost. To address this issue for the chemical reaction of adding hydrogen, called hydrogenation, to quinoline, a molecule important in pharmaceutical production, researchers based in China have developed a highly effective catalyst comprising synergistic nanoparticles and single atoms of iridium.