Second language confidence (L2C) is considered a central component in language learning as it can affect the processes and outcomes of second language acquisition (Dornyei, 2005). According to the functional model proposed by Sampasivam and Clement (2014), the two determinants that build towards L2C are "self-involvement" and "richness" of the contact experience. This study adds to previous research (e.g., Soyoof, 2018; Vincze & Joyce, 2018) by investigating, for the first time, the role of interlocutor type in the context of videoconferencing on the development of L2C in L2 and HL learners of Spanish. The research questions that guided this study were: (1) Does interlocutor type (i.e., a peer on "Zoom" or a native speaker on "Talk Abroad") play a role in the development of L2C in L2 and HL learners? Also, do these results vary over the course of the semester? (2) Are there differences in the participants' perception of interlocutor type in terms of "richness" and "self-involvement" of the language contact? Also, do these results vary over the course of the semester? Both the L2 learner (\uD835\uDC5B= 32) and HL learner participants (\uD835\uDC5B= 7) were students enrolled in a fifth-semester Spanish conversation course at a large, public U.S. university. Throughout the 16- week semester, they completed eight 30-minute videoconferences, four with a peer (L2-L2, HL- HL) on "Zoom" alternating with four with a trained and paid native speaker on "Talk Abroad." The participants were provided instructions for each conversation, with the topics directly corresponding to course themes. In addition to the conversations, data also comes from the participants' responses to an initial 29-item L2C questionnaire and eight post-conversation questionnaires including the original 29 items, 15 additional Likert-scale items, and 6 open- ended questions. The results of this study suggest that the participation in multiple peer videoconferences promotes both L2 and HL learners' Self-Perceived Linguistic Ability and Self-Assurance over time. These outcomes can be explained, to an extent, by the integrated model of L2C proposed by Sampasivam and Clement (2014) given that both communicative contexts (i.e., HL-HL and L2-L2 peers) were perceived by the participants as prompting "self-involvement," although they were not rated highly in "richness." Regarding the virtual interactions with NSs on "Talk Abroad," they were rated highly in both "richness" and "self-involvement" by both participant groups. In line with the theoretical framework, the L2 learners showed longitudinal increases in both factors of L2C as a result of interacting with NSs. However, interacting with NSs did not affect the HL learners' L2C development, which cannot be explained by the existing model. Overall, the findings of this research indicate that videoconferencing can pique language students' interest and increase their exposure to linguistic forms, and, thus, is recommended as a course component to promote gains in L2 and HL learners' L2C. Also, the intermediate-level participants in this study reported other benefits of the intervention such as its capacity to provide a context for practicing the target language and extensive reflection on course unit themes. Whereas the functional model of L2C was found to accurately explain the results for the L2-L2 peer dyads, NS-L2 learner dyads, and HL-HL peer dyads, it did not suitably apply to those of the NS-HL learner dyads. Thus, future research should ascertain the qualities of a contact experience that most effectively facilitates the HL learners' L2C development, especially given that fostering HL learners' confidence is critical for the heritage language's vitality (Sanchez-Munoz, 2016). Provided that remote learning is more commonplace than ever, this research is particularly relevant as it investigates the impact of technology on L2C development with the objective of informing pedagogical practices, however more research is needed to affirm these results and to answer the questions that remain. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]