The aim of the paper is to present and explain the key factors which play an important role in project management. Project success can be defined and analyzed from the various points of view, also from the perspective of a project product. Analyzing the conditionality and key factors which are most conducive to the achievement of a successful project, the particular attention was paid to the factors appearing in surroundings and resulted from external stakeholder influence on a project, which can't be predicted and controlled. The second area of discussed issues is related with the correct project planning, which helps to coordinate action on the realization of established purposes. The conclusion can be expressed by the statement that crucial success factors should be perceived in complex approach, noticing mutual interactions and feedbacks occurring between them.