Abstract What makes a material suitable for applications in the medical device industry? It is a question often asked, but seldom answered in a definitive way. This paper examines vinyl compounds from various viewpoints and attempts to define the requirements for their medical use with respect to formulation, chemical and mechanical purity, and performance characteristics such as viscoelastic properties, appearance, sterilizability, shelf life, and biological safety. Primary consideration is given to the situation in the United States, with a brief review of the position of some other countries' regulatory agencies. An outline is presented of how material suppliers can assure their customers and the regulators about the suitability of the compounds in question for various applications.