The main European instrument dealing with encouraging employment growth, improving the education system, workforce mobility, public administration efficiency and lifelong learning is the European Social Fund. This final paper analyzes the specifics of the implementation of projects co-financed from their funds through which the stated goals are achieved. Within the Operational Programme Efficient Human Resources 2014-2020 it is explained which legal framework defines the implementation of projects. The paper contains descriptions of project application conditions, basic rules and responsibilities of the user, and the obligation to respect visibility signs during the implementation of the project. The users obligations for individual phases of the project have been elaborated, with an emphasis on the importance of respecting horizontal priorities when carrying out activities. Furthermore, the procurement plan for projects of this type, the concept of budget, and the acceptable and unacceptable costs of the project are specified. In the empirical part of the paper, a concrete example of the project "Ja sam PAUK (Ponosan, Aktivan, Uključen, Koristan)" of the Association of Veterans of the 4th Guards Brigade of the Operational Programme "Efficient Human Resources" financed by the European Social Fund was analyzed. This part of the paper shows the specificity of the implementation of the project described in the first chapter on a practical example. The introductory part of the chapter describes the work of the Association and the way in which the idea of the project itself came about. Then, the method of its application, public procurement and ultimately the implementation of project activities was explained in compliance with all prescribed rules and project results. In the final chapter of the paper, the final thoughts on the implementation of projects of this type, the success of the project from the above example, and the impact that projects financed from the European Social Fund have on the general good of the Republic of Croatia are presented.