Pii: S0737-6782(02)00175-3

An abundance of IT innovations are constantly struggling for market acceptance. Various models have been proposed in the literature in order to aid understanding of the principles behind the adoption of IT innovations, but most of them implicitly assume that the factors explaining adoption decisions do not change over time. This study challenges that assumption and adds to the existing literature by investigating the dynamics of the factors influencing adoption. Our general proposition is that the driving factors in adopting innovations will change as the diffusion of the innovation in the market progresses. A large-scale empirical study was carried out among medium-sized companies in a variety of European countries and industries concerning the adoption of enterprise resource planning (ERP) software. The findings strongly indicate that the factors affecting late adoption of ERP differ significantly from the factors explaining early adoption. At early stages of the diffusion process adoption tends to be especially driven by a combination of internal strategic drives and attitudes of the firm together with external forces like industry competition and supplier activities. Later on, the mix of adoption stimulating factors seems to be focusing more on implementation issues such as the scalability of the system, the number of seats and the yearly available budget. The study leads to both new methodological insights and substantive conclusions that also have practical implications. © 2002 Elsevier Science Inc. All rights reserved.