Project management profession encounters numerous challenges in today's global environment. It is a known fact for every project management professional that most common challenges are the completion of project on time, scope changes, goals, unplanned risks, engagement on several different projects, lack of competencies, lack of top management and stakeholder engagement, economic instability, legal barriers and many others. Through literature search, it was observed that there are no data related to challenges project managers face in Serbia, and for this reason, the aim of this paper is to provide this information, based on a study conducted. Challenges presented in the survey are most widely and statistically recognized ones as globally present, and the idea was to show how these challenges fit into contemporary project management practice in Serbia and to show the difference between small and large companies. The research part of the paper was based on a survey, presented to project managers in project management practising organizations in Serbia, large majority of which being from a service sector. Through this survey four hypotheses were tested. Methods of descriptive and analytical statistics were used for evaluation of the survey, and all four hypotheses were confirmed. Major challenges for project managers in Serbia were identified, and it was shown that the size of a company does have an impact on dealing with challenges. Based on the data provided decision-makers in organizations will get a clearer understanding of real challenges in project management in Serbia, which should allow for better decisions.