It is shown that group theory may be useful in relation to dimensional analysis. The group theoretical support of dimensional analysis in universes described by kinematic groups is analysed. Its close relation to the structure of the corresponding kinematic group is also displayed by means of a simple dimensionalisation hypothesis. The scheme of contractions relating the kinematic groups enables one to discuss the dimensionalisation method. The same problem is also looked at in a different way: the possibility of adding dilatation-like transformations is studied. Finally, the role of mass in both relativistic and non-relativistic theories is examined.