Transgenic plants provide a viable technology for producing industrial proteins. Advantages of plant production systems include low cost of goods, stable protein storage in seeds, ease and speed of scale-up and the possibility of direct addition of plant material to industrial processes. Using transgenic plants for production of proteins includes several steps designed to result in high expression of foreign proteins-from gene manipulation to breeding. Characteristics of four protein examples are presented -beta glucuronidase, avidin, laccase and trypsin. These proteins represent a range of molecular weights, activities, and localizations, demonstrating the versatility of the system. The benefits of transgenic plant technology for industrial enzyme production include replacement of chemical processes that cause environmental pollution.