It is estimated that public purchases, at various levels of government, move about 10% of the Gross Domestic Product (GDP). Taking into account that the government is the largest buyer in the country, this study aims to verify the challenges faced by micro and small enterprises (SMEs) to participate in bidding processes, as well as the strategies used by them to address these processes. For that, an exploratory study was carried out, with a qualitative approach, of the case study type, using as a research tool an interview script applied to 21 SMEs and individual micro entrepreneurs (MEI, acronym in Portuguese). The results showed that MSEs and MEIs use the lowest price as a strategy and that the main challenge is to maintain the provision of services or the supply of goods or merchandise even with late payments.