Pharmaceutical product development and production as it is now practiced entails a sequence of scale-ups, beginning with tiny amounts of material for early safety or clinical tests and progressing to a manufacturing plant to provide commercial supply. Pharmaceutical manufacturing is a branch of the pharmaceutical industry that involves the manufacture of pharmaceutical medications. Product development in the pharmaceutical industry differs from product development in other industries. Pharmaceutical product development is primarily empirical, tedious, and time and resource consuming because the science and engineering of product development for pharmaceutical products is not as evolved as, say, for the chemical industry. Despite billions of dollars invested in production by the pharmaceutical industry, this is the primary cause of why the pharmaceutical manufacturing industry is still behind.