Latino English varieties, especially Mexican American English (henceforth MxAE), have received a considerable amount of research over the past six decades. In spite of that, they are still poorly understood in most respects. The reasons are numerous: most of the research has consisted of studies of limited scope, a fair amount of it was published in obscure venues, the issues of Spanish maintenance and of code switching often seem to overshadow Latino English in research efforts, Latino communities are widely dispersed across the United States, and there is a host of social issues that complicate exploration of Latino language varieties even as they enrich it. One aim of this book is to help rectify the weak understanding of Latino Englishes and MxAE.We cannot aspire to answer every possible question about Latino Englishes or even MxAE by itself. No study could address the entire myriad of such issues. In addition to clarifying issues regarding Latino Englishes, however, a second aim we aspire to accomplish is to draw scholarship on Latino Englishes into the more general body of research on language transfer and new dialect formation. To do so, it is necessary to take a primarily linguistic perspective, with the development of linguistic variables as the primary focus. Several groundbreaking studies, notably Mendoza-Denton (1997, 2008), Fought (1999, 2003), and Eckert (2008b, have taken a micro-variation approach, examining how patterning of specific linguistic variables in Latino communities is intricately tied to interpersonal networks and individuals' identity construction. These studies have provided vital insights. Here, however, we focus on the language as a whole and how it evolves from a collection of interference features to a stable dialect. Studies of substrate influences on languages typically focus, as the present study does, on linguistic features, appealing to social 1