Businesses and managers everywhere are finding out that using the classical investment analysis methods is not enough to cover their need for smart decision-support for high risk, hard to estimate investments under vague information, such as investments into R&D, IPR, and any other strategic projects and assets. This book introduces the pay-off method and shows how the method can enhance investment analysis and decision-support in a profound way. The pay-off method and a selection of tools within the pay-off method arsenal, including real option valuation, are simple to use, transparent, no-nonsense, and intuitive to understand. This book explains the pay-off method in detail and shows with many numerical easy-to-follow examples how the method can be applied in real-world decision-making in different industries. This book shows also how decision-making can be enhanced by visualizing imprecision and how real option valuation can be performed simply. All method presented are easily implementable with the most commonly used spread-sheet software. The pay-off method is a clear continuation to where the "old" investment analysis methods usually leave uss off and gives you a chance to better plan and to understand your investments. After having read this book you will never be the same decision-maker again, but you will know what information to require for better investment decision-making.