Providing foreign language students with opportunities to engage in meaningful and purposeful communication and culturally authentic interaction with peers and native speakers is critical to successful second language acquisition and the development of intercultural competence . This paper describes research that investigated how selected native speaker mentors supported foreign language university students as they completed authentic collaborative tasks in an online community of learners. Intermediate and advanced level students of Italian at an Australian university collaborated with each other and with their assigned mentors through online resources provided in the course website. Data were collected and analysed through multi-data sources including online interactions, forum posts and individual and focus group interviews with mentors and students. Findings suggest that native speaker mentors actively supported students' learning and provided effective scaffolding across a number of domains. The paper concludes with specific recommendations to guide mentors and language educators in the process of assisting student collaborative learning.