Regulations, the sanctioning system, and police supervision are among the main components for increasing road safety. In fact, most accidents are caused by non-compliance with the rules, and it is precisely the elimination and deterrence of these offending behaviors that must be based on an effective sanctioning system supported by the corresponding police supervision. This paper discusses some of the principles that enforcement must comply with in order to maximize its usefulness. To this end, this paper presents a series of empirical data from our own research, through surveys of the population (in Spain and the Dominican Republic), on the degree of knowledge of traffic regulations, the motivations that lead to compliance/non-compliance, as well as the penalties associated with non-compliance, the attributed and real probability of being sanctioned, and their assessment of the whole system, including the attribution of effectiveness. Finally, the aforementioned evidence is compared with key principles of learning and behavior (especially punishment), to see to what extent they correspond, thus drawing some conclusions about the common existing deficits in the reality of enforcement systems in many countries, which present an opportunity for improvement.