The course introduces students to the main findings, theoretical models, and research methods in the field of second language acquisition and it surveys general issues such as the role of internal (e.g., native language, age) and external (e.g., input, context of learning) factors on second language development. The principal aim of the course is to promote discussion and critical reflection about the acquisition of Portuguese and Spanish as non-native languages and analyze phonological, morphosyntactic, semantic, and lexical aspects in the linguistic performance of bilingual speakers and learners of Portuguese and Spanish as a second language. The experimental component of the course provides students with experience in designing and carrying out studies in second language acquisition. Taught in English.