The paper examines the two-way relationship between external R&D activ
ities and internal R&D expenditures on a cross-section of Flemish R&D
active companies. The analysis extends the classical explanatory varia
bles like size, diversification, ownership structure and technological
opportunities to include the impact of various external sourcing stra
tegies. R&D cooperation and to a lesser extent R&D contracted out are
found to have a significant positive effect on internal R&D but only i
f the companies have absorptive capacity in the form of a full-time st
affed R&D department. At the same time, firms are found to be more fre
quently engaged in R&D cooperation, the more they spend on internal R&
D. (C) 1997 Elsevier Science B.V.