Drug discovery is usually the major function of the pharmaceutical industry. A key player is fundamental research often conducted at universities or research institutes, frequently supported by government grants or sometimes by private sponsors or charities. Those studies may yield a new understanding of a disease process. Drug discovery then undertakes to identify the right material exploit the new knowledge usually to block the disease or speed natural healing processes. Once active candidates are identified they must be thoroughly investigated to understand any toxic properties. Eventually proper dosage forms and therapeutic ranges must be determined. Clinical trials proceed in stages to demonstrate efficacy in patients and identify any problems such as side effects. Finally the drug receives approval by the FDA. Then physicians must be trained to use it usually through a variety of marketing efforts.