Knowledge sharing can enhance learning and help to build the knowledge workforce. This paper reports on a study of knowledge sharing behaviour among undergraduate students in Malaysia. Knowledge sharing was found to be influenced by the mechanisms used, various barriers to communication and the motivations behind knowledge sharing. The mechanisms include online communication, social interaction, off-campus activities and learning activities. It was found that problems with information and communications technology (ICT), lack of self confidence, external constraints, self-centredness and social attributes can create barriers to knowledge exchange. It is concluded that the motivation to share knowledge appears to be affected by relationships, rewards and the level of satisfaction with knowledge sharing activities. (Contains 1 note and 4 tables.)