Some environmentalists, however, have used "business ecosystems" as a way to talk about environmental issues as they relate to business rather than as a metaphor to describe the increasing complexity of relationships among companies. According to Townsend, business ecology is the study of the reciprocal relationship between business and organisms and their environments. The goal of this "business ecology" is sustainability through the complete ecological synchronization and integration of a business with the sites that it inhabits, uses, and affects.[19]