Sustainability is defined as "an integrated approach addressing the impact of the building on the environment over its life cycle and eventual reuse.  It meets the needs of the present without compromising the ability of future generations to meet their needs."  Green is more commonly associated with the 3 Rs - reduce, recycle, reuse. 

When considering sustainable characteristics of a product, considerations are given to the impacts of acquiring and transporting raw materials to the point of manufacture; of product production and distribution; of use, disposal, and potential reuse.  Sustainable products go beyond recycling and VOC content limitation.  Sustainable products meet established durability characteristics, do not contain harmful components such as heavy metals, known carcinogens; are more water and energy efficient during manufacturer; use less virgin materials where practical; generally have more than a single environmental characteristic; general provide some sort of return the investment; and many more considerations.