Recent research on Agile Manufacturing (AM) has examined its relationship with Total Quality Management (TQM), Just in Time (JIT), and different levels of firm performance. Mixed results have been reported, probably due to non-availability of well validated AM constructs. This research develops a 3-stage model and examines AM's direct and/or indirect relationship with common infrastructures, TQM, and JIT and its effects on different levels of firm performance in the context of the Pakistani industrial sectors, specifically the apparel export industry. Data is collected from 248 Pakistani apparel export firms and the model is estimated using structural equation modelling. The results indicate that common (internal) infrastructure and TQM has a positive relationship with AM specifically in the apparel export firms in a third world economy where the industrial sector is in a nascent state. Whereas, JIT relationship is positively mediated through external infrastructure, TQM and JIT did not seem to contribute directly in operational performance. However, this relationship is significant when it is mediated through AM. Market performance positively mediates the relationship between operational performance and financial performance of the firm. The implications of the findings for researchers and practitioners, looking at the industrial sectors in the developing world, are discussed and research directions offered.