The application of the proportionality system in Law No. 18410 has posed some challenges of certainty and reasonableness in the administrative action. These challenges are often not addressed by the administration itself with uniformity and regularity, partly because of the dispersion of criteria used by the different officials called upon to resolve a case, and in partly because it is a moderately regulated power with significant spaces for discretion. This document deals with these challenges, and how to look for criteria that allow us to find light in the application of the proportionality principle in sanctions, within the Administration, and in the control exercised by the courts of justice.