Although the globalization of industrial R&D processes has increasingly attracted management scientists and considerable work on R&D internationalization has been done since the 70s, important problems in organizing geographically distributed R&D sites have not yet been resolved. This analysis is based on 165 interviews in 31 technology-based multinationals from Switzerland, Germany, USA, and Japan conducted between 1994 and 1997. We describe the extent of R&D internationalization, its key drivers and principal impediments. Two trends are identified: (i) a geographic concentration on leading technology centres, and (ii) a tightened coordination of R&D units. Overlaying structures, superimposed to regional and functional structures, play a central role in overcoming current deficits in global R&D management. Organizational constituents of this structure are technology offices (Schering), technology management as a competence center (Schindler), central project offices (IBM), central project management (Bayer), project oriented career development (Bosch), virtual project management departments (Roche), and cross-cultural job rotation (ATR).