The purpose of this article is to discuss the relations between regulation, competition policy and consumer protection these relations in three key sectors of Brazil’s infrastructure: telecommunications, electricity and water supply. A study of the literature points to two general principles. First, the need for consumer protection depends on the 'degree of sovereignty' enjoyed by consumers, defined in terms of the cost of consumer organization, consumers’ ability to evaluate services, and the level of competition in each sector. Second, the less sovereignty consumers enjoy the more consumer protection institutions are involved with regulation agencies. The evidence for the Brazilian case apparently corroborates these points. In addition, it is important to stress that consumer complaints in regulated sectors seem to have increased more intensely than in others. The article is divided into three sections. Section 1 presents theoretical elements and aspects of the relations between regulation, competition policy and consumer protection evidenced by international experience. Section 2 analyzes the Brazilian experience and in particular the available statistics on consumer complaints about telecommunications, electricity and water supply, submitted to Fundação Procon-SP during the nineties. The last section points to possible configurations of the institutional relations between competition policy, regulation and consumer protection, showing how the existing configuration of these areas in the three infrastructure sectors discussed confirms that the theoretical framework proposed has reasonable predictive power.