The control of adhesion properties is critical for many industrial applications. The precise determination of the surface free energy has however proved challenging either experimentally and with molecular dynamics simulations. A review of the existing techniques has been carried out and the most interesting approaches have been tested on several case studies. A comparison with experimental results has been conducted throughout all the work. The results showed the capabilities of these approaches in providing understanding of the adhesion at the molecular scale and the possibility of modifying these properties with the chemical composition of the surface. In detail, the approach adopted for the determination of adhesion through wetting properties proves very promising and further studies could lead to an extension of the scales of application.