The 1988 Constitution of the Brazilian Republic mandates that the States and the Federal Union provide full and free legal assistance to every citizen in need, through the Office of the Public Defender. The following study seeks to develop a better understanding of this Brazilian model of constitutionally mandated legal assistance, and determine whether it is really the best mean of assuring full access to justice for every person, regardless of their financial means. The study approaches this issue from an historical perspective, with reference to the constitutional and statutory legal system operating in Brazil, requiring full legal assistance to the poor (i.e. legal advice and right to counsel in civil and criminal cases), as well as the rules that govern the operations of the Public Defender`s Office. We will also review alternative models of free legal assistance offered in France and the United States. These systems were selected not only for their historical influence over Brazilian political and judicial institutions, but also because they reveal diverse characteristics in their judicial systems that broaden the horizon of our study. In two consecutive seasons of ethnographic research (participant and no participant observation and interviews), six months in the USA, and six months in France, we are able to closely observe the day-to-day functioning of these two models of legal assistance, with visits to offices, interviews with key figures in the judicial system, and an extensive bibliographical review of the literature on legal assistance in the respective countries. Through this critical historical and normative analysis of the operation of these two foreign systems of legal assistance to the poor, we believe it has been possible to throw into greater relief the virtues and defects of the Brazilian model. We hope that this study will produce a deeper understanding of the national model of free and comprehensive legal assistance established in the Brazilian Constitution, and encourage those responsible for administering the system to optimize its virtues and overcome its defects to better achieve its goals of equal access to justice and the guarantee of the fundamental rights of all Brazilians, regardless of theirs social or economic condition.