This paper presents the results of a survey of micro-enterprises undertaken in Ecuador and Jamaica. The purpose was to understand the relationships between these countries' institutional and legal regulations, the degree of compliance by firms and the impact of compliance on their performance (particularly growth). This enquiry was complemented with case studies of issues related to compliance with regulations. Initially, the paper sets out to analyse the characteristics of the microenterprises surveyed and their type of insertion into product and factor markets. Afterwards, it describes the differences observed in the regulatory frameworks of the two countries, and explains the differences in the degree of compliance with the law on the part of small firms. The final part of the paper determines statistically the relative importance of the factors that influence firm registration and identifies their effects on the growth of micro-enterprises. The initial process of registration ...