The imposition of tax on income from financial capital raises controversy both in the literature of the subject and in practice. When attempting to assess it against the usual criteria, such as fiscal efficiency, fairness and impact upon economic processes, one can easily find arguments both in favour and against such a tax. The divergence of opinion is reflected in the divergence of practical arrangements. Comparative analysis of tax regulations in several dozen countries, including the EU ones, reveals that there is no commonly applied model. What matters is that the different regulations - to a greater or lesser degree - take into account the specific character of income from financial assets (its diversity, the risk involved, value of money in time). The creators of the Polish tax system also seem aware of the diversity of this income. Yet the particular solutions, as well as the general idea of systematically extending the tax to new types of income deserve serious criticism.

The capital market and income from capital are particularly difficult to tax. This is because tax regulations should not interfere with the process of capital allocation; at the same time there should be no loopholes which would facilitate tax avoidance. Fiscal authorities should keep this in mind both when creating the new tax and in the course of its administration.