The chemical libraries in larger pharmaceutical companies are a critical part of the discovery process. These chemicals are stored in environmentally controlled conditions in small or large containers, often labeled with codes that pass back into a database. Each chemical in the storage bank must be monitored for shelf life, quantity, purity and other parameters, and its banked location. In some companies, the compounds can also include biological compounds, such as purified proteins or nucleic acids. The management of these chemical libraries, including renewal of outdated chemicals, databases containing the information, robotics often involved in fetching chemicals, and quality control of the storage environment is called Compound Management or Compound Control. Compound Management is often a significant expense, as well as career for one or more individuals who manage a chemical library at a research site.