In polymer chemistry, chain walking (CW) or chain running or chain migration is a mechanism that operates during some alkene polymerization reactions.  CW can be also considered as a specific case of intermolecular chain transfer (analogous to radical ethene polymerization). This reaction gives rise to branched and hyperbranched/dendritic hydrocarbon polymers.  This process is also characterized by accurate control of polymer architecture and topology.  The extent of CW, displayed in the number of branches formed and positions of branches on the polymers are controlled by the choice of a catalyst. The potential applications of polymers formed by this reaction are diverse, from drug delivery to phase transfer agents, nanomaterials, and catalysis.