Large-scale interstate labour migration within India is facilitated by the freedom of movement for citizens within this huge nation state. However, such internal labour migration within India remains largely unstudied and offers huge scope for gaining significant new knowledge. Focusing particularly on migrant construction workers from West Bengal moving to Kerala, this article specifically examines the motivations of these migrants and the role of social networks in the development of such migration streams. A field survey in Kerala indicates that Kerala’s Gulf connection and rapid demographic transition have resulted in significant reduction of local supplies of labour, thus attracting more migrants from other states in India due to better job opportunities, higher wages and good payment systems. Networks within migrant groups, especially friends’ contacts, are found to be the strongest factor in supporting this migration process.