Polymer flooding is the most commonly applied chemical enhanced-oil-recovery technique. This paper provides an update on the status of polymer-flooding technology, focusing more on field applications than on theoretical and laboratory research. It covers the following topics: Mechanisms of polymer flooding Polymers used Polymer-solution stability Technical screening criteria Laboratory and simulation work Performance-monitoring technique Summary of pilots and large-scale applications Experience and learning from field projects Polymer flooding in heavy-oil reservoirs Polymer viscoelastic properties Problems associated with polymer flooding and their solutions Future developments The data and analysis presented in this paper will give readers updated information describing polymer flooding, as well as a guide to the relevant research. Survey data will also provide operators with reference data for project design and optimization.