Màster de Lingüística Aplicada i Adquisició de Llengües en Contextos Multilingües, Departament de Filologia Anglesa i Alemanya, Universitat de Barcelona, Curs: 2016-2017, Tutor: Júlia BarónInterlanguage pragmatics (ILP) is a thriving field within second language acquisition study. However, the role of assessment in ILP is troubled, with procedures that have been shown to produce inauthentic language use. The growth of task-based methodologies may provide an avenue for a new form of task-based pragmatic assessment. This study aims to investigate the use of a collaborative game task in eliciting naturalistic suggestion forms from English as a foreign language (EFL) learners. The task was used with four intact groups of EFL learners at different ages and different stages of proficiency, and the language obtained compared with roleplay data. Results showed that students at all ages and levels used simpler and more direct language in the game task, although the changes were not uniform. It is proposed that the greater consequentiality of the game task caused the students to produce more authentic language samples. For pedagogical purposes, use of both task types may best assist teachers to judge their students’ ILP development. For researchers, collaborative tasks may help elicit language subjects actually use, rather than what they think they might use.