1. Introduction Relevence of research. The correct choice of financial instruments is one of the most important criteria for a successful investment. Selection of companies plays an important role in whole capital investment chain. In such a turbulent environment of financial market to achieve specific goals investors are looking for new strategies, tools, and measures that would help to contain the increasing risk, while maintaining the same, or even greater than the market's profitability of the investment. To satisfy the growing investment needs, already created and argued out methods are being improved, the classical synthesis strategies are being created, that in many cases the existing results would be improved. So it is clear, that constant monitoring of stock, an appropriate choice of stock selection strategy is the most important tool to achieve the desired return on the investment portfolio. Economists focus and the lack of published researchs led the authors to investigate the selection of companies in the investment portfolio, based on the discounted cash flow method strategy that has the theoretical basis and practical application to the global capital markets. Research problem. How to select investments in the global capital markets, so that they won't exceed the tolerable level of risk, provide the highest return for such risks and guaranteed development of sustainable portfolio. Research subject. Investments, consisting of the global capital markets quoted companies stock. Research goal. To verify the individual financial assets as the financial elements of the system and to evaluate the benefits of the financial assets portfolio of those subjects who borrow this capital. Hypothesis. Investment selection by discounted cash flow method constitutes a premise to obtain higher than the market's return. 2. Grounded Theory and the Concept of Sustainable Development of the Financial System Emerging concept of sustainable development requires to take a look back at the failures of the financial system, pay attention not only to economic growth but also to pay the same attention to the ecological and social dimension. In the scientific literature (Ravichandran 2007, Stiglitz, 2009, Alfonso 2012, Castren 2010, Goodschild 2012, Sharma 2012, Thalassinos et al. 2013) sustainable development of financial system is often limited to the analysis of economic aspect problematic. For the authorss of the article, it became a challenge to find innovative concepts for sustainable financial system, its evolution and improvement solutions. In fact, talking about the environmental dimension of the financial system is extremely difficult, but based on the Grounded Theory model, could be returned to the concept of sustainable element. This concept became popular after Bruntlandt Commission in 1987 published the report Our Common Future. It is important to note that until now, this concept has not been fully disscused. Based on the fundamental concepts of the guidelines: enlargement of general level of these days and future generations welfare, minimization of these days level of risk, economic stability, efficient distribution of resources (capital), competitive and sustainable environment, the authorss proposed an innovative approach and a new concept of the global financial system's sustainability. Thus, based on the application of grounded theory in the financial system, its sustainable development and taking into account all of the above listed theories of sustainability guidelines, without exception comprising three the most important aspects of this concept, combining but not distincting these components, we will be able to take advantage of the Grounded theory and its methods applied. Grounded theory is important because it is extremely focused on finding the interpretation of the problem as a whole and of its parts. If going deeper into the origins of Grounded Theory, components of financial system and sustainability concept can be easily perceived, evaluated and combined. …