Inclusive design ultimately represents an innovative way of thinking about the built environment. Inclusive design is a holistic approach to the process of developing and creating products, buildings, landscapes, systems, and cities. The aim of inclusive design is frequently described in terms of outcomes, for example, a product or building being functional for and usable by the greatest percentage of the population possible. The development of inclusive design research and practice is contemporaneous with that of sustainability or "green building", and the two share considerable intellectual space. While inclusive design first and foremost needs to be seen as a way of working, it also needs to be viewed from both functional and aesthetic vantage points. The primary challenge for inclusive designers, then, is to build environments that meet people's evolving needs over the course of their entire lives. Inclusive design incorporates human factors, seeking to enhance life by reducing health risks and increasing convenience, comfort, safety, and usability.