Collocation is an aspect of language generally considered arbitrary by nature and problematic to L2 learners who need collocational competence for effective communication. This study attempts, from the perspective of L2 learners, to have a deeper understanding of collocational use and some of the problems involved, by adopting a task based approach, using two highly comparable corpora based on the writing of Hong Kong ESL and native-speaker British students. Results of the study indicate that the performance of the Hong Kong students in collocational use might be adversely affected by their L1, L2 as well as their inadequacy in the lexis and grammar of the target language. Findings of the study suggest the need for a broader view of collocational knowledge and a pedagogical approach to the learning and teaching of this aspect of L2. The implications for teaching English in general and English vocabulary in particular are also discussed in detail. (Contains 3 tables and 1 figure.)