This book examines the birth of punk in the UK and its transformation, within a short period of time, into post-punk. Deploying innovative concepts of 'critical mass', 'social networks' and 'music worlds', and using sophisticated techniques of 'social network analysis', it teases out the events and mechanisms involved in punk's 'micro-mobilisation', its diffusion across the UK and its transformation in certain city-based strongholds into a variety of interlocking post-punk forms