I think that a bit more clarification is needed in the question. The notion of "sustainability" is of vital importance in such a query and I think more along these lines is needed. As previously noted, the idea of a mission statement gives much in way of overall purpose and focus of the organization. The component of being environmentally aware can certainly be an integral element of a company's mission statement. The mission statement gives a sense of focus and direction to the organization. It can assist in economic sustainability, but the overall determinant of this might be more due to external factors such as viability in the marketplace or meetings needs of demand through supply.