The forecasts for the world and the UK economy reported in this Review are produced using NIESR's global econometric model, NiGEM. The NiGEM model has been in use at the National Institute for forecasting and policy analysis since 1987, and is also used by a group of about 50 model subscribers, mainly in the policy community. Most countries in the OECD are modelled separately, and there are also separate models of China, India, Russia, Hong Kong, Taiwan, Brazil, South Africa, Estonia, Latvia, Lithuania, Slovenia, Romania and Bulgaria. The rest of the world is modelled through regional blocks so that the model is global in scope. All models contain the determinants of domestic demand, export and import volumes, prices, current accounts and net assets. Output is tied down in the long run by factor inputs and technical progress interacting through production functions, but is driven by demand in the short to medium term. Economies are linked through trade, competitiveness and financial markets and are fully simultaneous. Further details on the NiGEM model are available on http://nimodel.niesr.ac.uk/.