摘要：The literature on the internationalisation of firms has paid little attention to SMEs. SME-oriented
studies are predominantly descriptive or illustrating theoretical arguments, and those dealing with
services are mostly confined to specific industries. The paper aims at correcting some of these
deficiencies. To this end, we start with characterising the international activities of Swiss-based
firms with special emphasis on differences by size and sector. The pattern we find for SMEs is
broadly in line with theory and (the somewhat fragmentary) empirical evidence. The main part of
our contribution is devoted to identifying econometrically, based on firm-level data, the factors
determining international activities of SMEs. The analysis confirms Dunning’s “Ownerhip-
Location-Internalisation” paradigm, with ownership-specific advantages being the main drivers,
irrespective of firm size, sector and internationalisation strategy (in terms of business functions
transferred abroad). However, we also find important differences by firm size: Location-specific
advantages foster international activities only in case of SMEs; internalising advantages are
relevant primarily for large firms; application-oriented knowledge and foreign experience are
particularly relevant ownership-specific advantages in case of SMEs, whereas R&D is an
ownership advantage of prime importance for large firms. Both the descriptive and the
explicative analysis imply that international and domestic activities are complements.
