The increasing consumption potential within the low income population is a phenomenon that has been gaining increasing prominence in both the business world and in academia. As consumption in this segment increases steadily, it is necessary to understand the behavior of these consumers, who have long been neglected by marketing. In particular, the aspects related to brand selection and the influence of price in the choice process are of particular interest to companies regarding the positioning of their offerings in an attempt to capture a share of this market. The notion that low-income consumers are brand-conscious gained momentum after the ideas launched by Prahalad (2005), but caution is needed to avoid generalizations. This dissertation sought to understand how low-income consumers form their consideration sets (select group of brands that consumers form to reduce the universe of options to a cognitively manageable number), and the mechanisms they engender to accomplish their final choices. Based on indepth interviews, the study investigated the factors affecting consideration set formation within typical FMCG categories. Findings show that six factors appear to influence the consideration and choice of brands within low-income consumers, and that each may act differently for each category and for each consumer. The study reveals that decision-making within low-income consumers assumes complex and specific contours, permeated by two vectors of opposite directions: the desire for quality, on one hand, and budget constraint, on the other. The notion that low-income consumers are brand-conscious cannot be generalized, since different motivations for decision making seem to exist for each category and / or groups of consumers.