The goal of this dissertation is to investigate the use of Google Translate (GT), a free online translation software that includes translation, Text-to-Speech (TTS), and Automatic Speech Recognition (ASR) functionalities, for online self-regulated learning of Mandarin Chinese within an interactionist approach. It also explores how GT can be used for pedagogical purposes within a complex learning environment that combines computer-assisted language learning (CALL), online self-regulated learning (SRL), and informed by interactionist theories. This dissertation begins with a review of the literature around the importance of interaction in language learning, followed by how a fully online interactionist approach using GT as a language partner and interlocutor allows learners to practice language use whenever and wherever they please (Chapter 1). Next, the dissertation contains three manuscript-based chapters (Chapters 2, 3, and 4) and a concluding chapter (Chapter 5). Each manuscript explores one aspect of using GT for pedagogical purposes by addressing the following overarching research questions: 1) Can GT provide the necessary computer-assisted interaction including input, output, and feedback to promote second language (L2) learning (Manuscripts 1 and 2), and 2) Are learners willing and able to use GT in an online, self-regulated environment for the learning of Mandarin and its associated tones? (Manuscript 3). 
	The first manuscript investigates the use of GT’s TTS as a source of Mandarin Chinese input when compared with a native speaker in terms of Intelligibility (how much is understood), Comprehensibility (how challenging something is to be understood), and Naturalness (how much does a synthesized voice differ from a human speaker). The second manuscript further explores GT’s ability to interact with a human interlocutor by investigating how much Mandarin Chinese speech can GT recognize at various language levels (intermediate, advanced, and native) and whether it can provide transcriptions accurate enough to be used as feedback by the language learner. The third and final manuscript investigate the pedagogical feasibility of using GT and its built-in features (translation, TTS, ASR) in an online, self-regulated environment by exploring how a small group of participants acquire language features, develop self-regulated learning strategies, and perceive the GT-enhanced pedagogical environment as a venue for language learning. 
	This dissertation will contribute to the literature around using translation, TTS, and ASR software for language learning, as well as interaction theories, SRL, CALL, and the acquisition of Mandarin Chinese in general. This research innovates on existing online language learning research and interactionist approaches by positioning GT as an interlocutor despite its intrinsic limitations (it is after all, not a human). This dissertation will further help guide future research into how human beings can interact with computers for language learning and will only become more relevant as translation, TTS, and ASR software becomes more intelligent, capable, and life-like.