The paper proposes a systematization of the key success factors of projects, through the theoretical review of family-owned companies operating in the EU market. It is the small and medium companies that in their own way contribute to the overall success of the national economy in terms of economic activity, increased employment, development activities and defining better business environment. The theoretical review observed numerous studies of family businesses, and the contribution of this work is in the systematization of the results of previous research – over three horizons, i.e., over the role of managers in the creation of successful projects (or owner if it is a family enterprise), institutional support for companies in Serbia and the EU, specific industries and the parent (regional) markets where a family company operates. Project management, as a general representation of the concept of implementation of strategic and operational endeavors, contains many specifics in terms of critical success factors of projects depending on the environment in which they are implemented. The goal of the paper is reflected in the identification and presentation of critical success factors of projects implemented in family companies. The paper concludes with a discussion of the research results in relation to the existing, similar research studies, as well as with the announcement of future research, which will examine the conclusions drawn on a real sample.