This first volume of a two-volume publication presents detailed data on the industrial activity of multinationals in OECD countries. In an era of globalisation, these data highlight the increasing importance of multinationals in the economies of host countries. Time series cover 23 countries for the period 2000-2004.  This volume provides data for the manufacturing sector covering 18 variables including production, employment, investment, research and trade. Volume II provides similar data for services. These data provide a measure of the impact of foreign direct investment on the economies of the OECD countries. From this standpoint, they provide a vital backup for data on direct investment flows.This publication includes StatLinks, URLs linking to Excel® spreadsheets containing the underlying data.