The 21st century is seeing new mineral resources in ever more sensitive locations coupled with growing opposition to mining activities, increasing demand, continuing social inequality and greater competition for technical skills. These challenges are further compounded by the changing nature of society's expectations of business. Low levels of trust in business in general and the historically poor reputation of high-impact industries in particular is prompting increased public scrutiny and greater regulation of commercial activities - and the need for greater transparency and accountability.A particular challenge facing mining companies is achieving mine closure and relinquishment. The difficulty in achieving closure is often tied to an inability to meet environmental and social commitments made through the life of the mine. Mines are often overly optimistic about their ability to achieve closure, and the risks are not well understood. In addition continuous engagement with stakeholders over the life of mine is essential in order to identify expectations and interests. Critical to successful mine closure is that rehabilitation must be integrated into the mine plan, rather than a standalone closure plan. In addition, stakeholder expectations often change towards the end of the life of mine leading to sometimes significant cost increases to achieve closure. As a result, closure provisions often fall short of the true costs of closure and closure provisions are insufficient.Properly understanding and valuing closure requirements at the option analysis stage of projects can have a major impact on the relinquishment post-production and increase the net present value (NPV) of the mine. Measuring the potential financial and non-financial value that can be created or eroded due to sustainability challenges and opportunities over the life of a mine is therefore becoming an imperative. By placing a financial value on sustainability considerations, decision makers gain a far better understanding of the value at stake associated with key decisions, which results in enhanced decision making, delivering projects with greater confidence, improved quality, increased shareholder value and less uncertainty associated with closure.The keynote address will cover these aspects through a case study of The Oaks Mine in South Africa. This mine is an open pit diamond mine for which concurrent rehabilitation was part of the mine's design with waste rock and mineral residue being co-deposed to achieve the end-state during the life of mine. By integrating the concept of closure from the start, this minimised the need for extensive and costly earthmoving after production ceased. In the closure phase, the focus was on ecological restoration and removal of remaining infrastructure to enable the area to be considered for game ranching. To enable economic sustainability, the company continued its support for many organizations and programs covering health, education, transportation, sports and community welfare. Training helped former employees of the mine and their communities to exploit new opportunities in mining and other sectors. At closure, two-thirds of the permanent employees had been redeployed to other company mines.*This is an abstract only. No full paper is available for this abstract.*CITATION:Lingenfelder, D, Wickens, P and Churr, A, 2014. The value of sustainability - making informed decisions, in Proceedings Life-of-Mine 2014 , pp 23-24 (The Australasian Institute of Mining and Metallurgy: Melbourne).