This chapter introduces the idea of a continuum of Portuguese in Africa and Brazil. It further identifies the common research questions, presenting earlier studies and discussing current gaps in research about Brazilian and African varieties of Portuguese. A detailed overview of the book explains how each of the contributions works towards informing these questions. Finally, in the final remarks, the authors suggest further research questions, and put forward the necessity of developing a corpus that includes a diversity of points along the Afro-Brazilian continuum, i.e. datasets with the potential to inspire comprehensive descriptions as well as fine-tuned analyses of the linguistic properties and sociohistorical settings of the continuum. Moreover, this introduction signals the need for supplementary research on exactly which linguistic groups have cohabited where, and in which conditions, and for further exploration of the weight that each of the languages in a particular setting has had in the competition created by each contact situation.