This chapter provides an overview of research on stable social grouping in lizards, focusing on contributions and future directions. It explains a detailed overview of patterns of stable social grouping in lizards and outlines the factors which may have led to their emergence, and diversification within this structural grade of squamates. The chapter discusses the role that lizards may play in researchers continued quest to understand when, where, and why animals live together. Social behavior per se has been relatively well studied in lizards, beginning with D. W. Noble and H. T. Bradley’s monograph of lizard mating behavior and sexual selection. Social groups in lizards take several forms, in terms of both their genetic makeup and the extent to which they represent stable entities. Lizard social organization assumes two main forms: egalitarian social groups and fraternal social groups. Social grouping in lizards, particularly that associated with fraternal social groups, appears to be accompanied by several of these life history traits.