As language acquisition research supports the value of the interactive scaffolded environment and awareness-raising communicative tasks for the development of pragmatic knowledge, the present study attempted to investigate the effect of Collaborative Translation Task (CTT) on learning and retention of request speech act strategies. The main objective of the study was to determine whether collaborative translation tasks, either from or to the target language, presented in a supportive expert-novice environment, might lead to more efficient learning and retention of pragmatic knowledge. For this purpose, an experimental study was designed with four experimental groups and one control group, receiving different types of treatment including CTTs, and structured input with and without explicit instruction. Three equivalent forms of discourse completion tasks (DCT) were given to 150 low-intermediate participants as a pre-test, a post-test and a two-month follow-up delayed post-test. The results of the study indicated that CTTs appeared to have enabled noticing and deeper processing of both pragmalinguistic and sociopragmatic knowledge and resulted in improved learning and retention of pragmatic knowledge. The results also provide positive evidence for House's (2008) hypothesis that translation has the potential to raise pragmatic and cross-cultural awareness.