In this review, the experimental evidence supporting the fact that the cell adhesion molecules N-CAM and N-cadherin are involved in myogenesis has been surveyed. In order to give access to the function of these molecules, a strategy of in vivo localization and in vitro perturbation of their adhesive function by interfering antibodies and peptides was applied. Both molecules are expressed at the surface of myogenic cells during myogenesis in vivo and in vitro. The blockade of the N-CAM adhesion function leads to a mild reduction of the rate of myoblast fusion, while the inhibition of the N-cadherin function induces a drastic inhibition of fusion suggesting that N-cadherin-mediated adhesion is a critical step in the process of myoblast fusion. Both molecules are re-expressed during muscle regeneration suggesting that adult myogenesis is under the control of the same adhesive systems as embryonic and foetal myogenesis.