Often differences in the purchase price between a non-sustainable and sustainable alternative are negligible. Yet even where the sustainable option costs more upfront, savings of energy, water and waste over the lifetime of the product or service can provide significant financial savings. On a macroeconomic level, it can be argued that there are economic benefits in the form of efficiency gains from incorporating whole-life costing into decision-making. (Note: in contrast to most arguments from sustainable procurement proponents, these can be purely private benefits accrued by the procuring organization.)