Innovation is omnipresent in today's world. Yet, our understanding of innovation from a value chain perspective has so far been piecemeal. The present paper aims to address this knowledge gap by conducting a systematic and narrative review of the extant literature on innovation value chain. The review in the paper sheds light on the trajectories of innovation from a process to value chain perspective and highlights the elements that characterise the innovation value chain, namely knowledge sourcing, knowledge screening, firm-level knowledge diffusion, business model, realisation. The 'what', 'how', and 'why' of each innovation value chain element are also discussed, thereby reconciling fragmented knowledge and providing greater clarity on innovation value chain.