Researching the importance of foreign direct investment (FDI) in today’s conditions of globalisation, integration and regionalisation is a topical and interesting subject, in particular, from the aspect of transition countries and change that has taken place on the international market of goods, services and capital in recent years. For a number of decades, FDI issues and the activities of multinational corporations have occupied scholars, and rapid changes to the world market, economic systems and the setting up of new economic relationships have brought about the need to consistently monitor and supplement various elements of the theory that has not, since its inception, demonstrated a singularity in its line of development. Entering upon and developing international operations has become a “survival” issue, not only at the level of businesses, but also at a considerably broader level. Attracting and creating multinational corporations are becoming key elements of competitiveness and economic growth, in particular within integrations such as the market of the European Union (EU), within which all countries are becoming increasingly similar with regard to size and relative amount of production factors, the capabilities of human resources, and the technology they use. The research subject of this doctorial dissertation is about associating outward FDI issues and economic growth. The basic task of the dissertation is to investigate, define and test the determinants of outward FDI that foster faster economic growth in transition countries. Scientific methods have been used to explore the fundamental hypothesis of the positive effects of outward FDI on the economic growth of transition countries; this hypothesis is elaborated upon in detail through a macroeconomic and microeconomic approach to studying outward FDI. Encouraging the creation of multinational corporations is a strategic target of development. Knowing and understanding the determinants of outward investment activities is fundamental to creating multinational corporations, while inward FDI, as a knowledge source, increases the likelihood of outward FDI, as proven empirically in the macroeconomic model of outward FDI. Regional FDI distribution points to a dominance of advanced countries, these being the world’s largest FDI recipients and providers. Relative to earlier capital flow, capital flow within specific regions is now evident, capital is increasingly less restricted by national borders, and the primary criteria for capital flow is to generate profits. Accordingly, transition countries are attractive to international capital not only as a large potential market, in particular, upon their accession to the EU, but also as a source for exploiting less costly production resources – their educated work forces, above all – thus impacting on the increase of business efficiency. Transition countries need to understand this FDI trend as a development process, and in their current development phase, they must take full advantage of foreign capital and all positive effects of inflow that can help them to assimilate new knowledge, skills and technology, foster competitive relationships between suppliers and buyers on domestic markets, adopt up-to-date production processes, introduce new ways of communicating with end consumers, and so on. Transition countries need to be quick in assimilating the experience of advanced countries. This mean that they must assimilate a huge amount of knowledge and many new technologies in the shortest time possible, this being the only way possible to survive and develop in modern conditions in which the instrument of outward FDI plays a vital role as an engine of economic growth. From these theoretical concepts are derived the basic elements that need to be built into a model of outward FDI and economic growth and which should provide an answer to the question: Which determinants are important in increasing outward FDI in transition countries and, at the same time, impacting on their economic growth. The basic model includes determinants that express: (i) a country’s level of economic development and (ii) the specific features for economic development in transition economies. The outward FDI model includes the following variables: inward FDI, per capita Gross Domestic Product, degree of openness, inflation, balance of current accounts, foreign exchange rates, number of Internet users and upward/downward trends in monthly salaries. The model formulated was tested using the fixed-effect regression model as an econometric method, and the following conclusions were derived: 1: An increase of foreign investment in transition countries impacts on the increase of investment by transition countries in foreign countries. This is the model’s most important determinant. 2: An increase in the level of economic development and living standards of domicile populations impacts on the increase of outward FDI of transition countries. 3: The advancement and assimilation of technology by a country fosters the increase of outward investment of domestic corporations. In global terms, intangible production resources are of dominant importance. 4: A reduction in the foreign trade deficit impacts on the increase of outward FDI, as a result of a rise in productivity and growing exports. 5: Contrary to expectations, the openness of the national economy is a negative determinant, meaning that the heightened involvement of transition countries in the flows of international exchange impacts on the decline of outward FDI. 6: Instability in a country and pronounced price changes demonstrate that instability leads to flight of capital from the country, that is, to an increase of outward FDI. 7: The remaining two determinants included in the model: (i) foreign exchange rate and (ii) upward/downward trends in salaries are of no statistical significance. A rise in foreign exchange rates (rate appreciation) will lead to an increase in outward FDI. An increase in labour costs in a country will also be a motivation for setting up businesses abroad. A more detailed elaboration of a microeconomic model of outward FDI is based on the hypothesis that multinational corporations are agents of internationalisation that, according to their characteristics in terms of ownership, location and internationalisation, make decisions on how to enter international markets. In this, the role of the government and government policies is limited and liberalised in today’s conditions of integration and regionalisation. Macroeconomic conditions provide a framework for microeconomic decisions of multinational corporations, which are predominant. The model’s independent variables include the essential elements of a firm’s business operations that determine its decision to either operate within the national economy or to export and/or invest abroad, thus redirecting a part of production (operations) onto the foreign marketplace. These are elements that define: (i) the quantity of a firm’s tangible resources and (ii) the quantity and quality of a firm’s intangible resources. Based on the econometric probit and logit (regression) analyses carried out, the following conclusions can be derived: 1: The value of a firm’s material assets and the number of its employees, that is, a firm’s tangible assets exert a positive influence on its decision regarding FDI. 2: Technology has a positive influence on the decisions of Croatian firms regarding FDI. 3: Productivity shows a positive and significant relationship and exerts an influence on the increase of outward FDI, as predicted by the Helpman, Melitz and Yeaple model. 4: The potential and quality of human resources has a significant positive impact; the potential of human resources, together with an export orientation and innovation, is an indicator of the “level of development” of a firm’s intangible assets that are vital to achieving outward internationalisation. 5: An export orientation has a positive and statistically significant influence on a firm’s decisions regarding FDI and it encourages the outward internationalisation of Croatian firms. 6: Innovation has a positive impact on outward internationalisation, despite not being a statistically significant indicator. Increased investment in research and development exerts a positive effect on a firm’s performance indicators. 7: Foreign ownership has a positive and statistically significant impact on the foreign investment trends of Croatian firms. Qualitative econometric analysis has confirmed on the example of transition countries that the expansion of multinational corporation activities in foreign countries calls for a required quantity and quality of tangible and intangible production resources. In comparison with a corporation’s tangible resources, knowledge-based assets such as the potential of human resources, innovation and export orientation are the more important determinants of outward internationalisation.