It’s the touching story of when protein meets ligand: bonded by hydrogen bonds and hydrophobic contacts, the pair can go on to regulate gene expression, facilitate cell signaling, or mediate metabolism. The Protein Ligand Database (or PLD, as insiders in the business like to call it), developed at the University of Cambridge, is a nice database for researchers interested in studying the nature of protein-ligand interactions. Currently containing 485 protein-ligand complexes, the database continues to be expanded. One can search by protein name or function, ligand name or origin (natural product versus xenobiotic), or by interaction type. There are also tools available to view experimental and predicted binding energies. With a simple design, the website is easy to navigate. This is a good resource for researchers that will continue to improve as the database expands.