[en] Electromagnetic surface waves dissipate energy as they propagate in plasma columns. The transfer of energy to the discharge generally occurs through collisional processes -hence the name ''collisional'' surface waves. It affects the direction of propagation of the wave, and is responsible in particular for the turning back of the axial wavenumber on the phase diagram. The rate of collisions also influences the respective contribution of surface waves and radiation (unguided) waves to the total electromagnetic field. These considerations are of interest in improving the reliability and accuracy of the electron density diagnostic based on surface waves. This paper takes advantage of the many articles published in the domain of guided waves for antennas. (Author)