In front of traditional interpretations of the digital gap based on endogenous conditions of the firms, this chapter intends to emphasize the importance that some external pressures may have on the ebusiness strategy of small and medium enterprises (SMEs). The environmental factors analyzed here are market position, competitive intensity, and institutional pressures. SMEs have been grouped according to their level of e-business involvement, in relation to the number of e-business solutions adopted so far. Three layers are proposed: excluded, tentative, and integrated e-business SMEs. A multinomial logistic regression was used to predict these strategies. A general conclusion is that different models seem to explain exclusion and involvement. Specifically, two factors among those analyzed reveal to be more suitable in explaining e-business exclusion. They are the size of a SME and a lack of institutional pressures to adopt. On the other hand, e-business involvement seems to be primarily prompted by a selective competitive environment and not by imitative behaviors, as in the previous case.