In this chapter, we provide an overview of previous studies of the rhotics in Peruvian Spanish, in both coastal and Andean varieties, followed by a description of the social and contextual factors that influence assibilation. We then describe a study of dialect contact in Lima, focusing on assibilated /r/ in the speech of 40 residents of Lima, comprising first-, second-, and third-generation Andean migrants, as well as classic Limeños. A multivariate analysis showed that migrant generation was the strongest factor conditioning /r/ assibilation in Lima, with the highest probability of assibilation occurring in the first generation and to a much lesser degree in the second generation. The third generation assibilated even less than classic Limeños. Regarding linguistic factors, assibilation had a greater probability of occurrence when /r/ was in initial position and when preceded by a sibilant. We conclude with the implications of this study for language change in Lima and provide suggestions for future research.