This study compares Quebec's tax effort with that of the other Canadian provinces. The results show that the tax effort is higher in Quebec than in any other Canadian province. In the first section, the authors expose the global situation that currently prevails in Quebec. In the second section, an analysis of the tax effort for six tax bases is carried out. Those six bases are equally divided between individuals and corporations. The analysis makes it possible to identify the tax bases where the gaps are the largest. This in turn lets us identify achievable adjustments within Quebec's current tax structure in order to attain a comparable structure with the other provinces, if such is the wish of the present government.