We explore the context-specic determinants of broadband takeup among small-and medium-sized enterprises (SMEs), attempting to shed some light on the sources of the considerable geographic variation in particular. We begin by discussing the determinants of broadband adoption as identied in relevant literature, relate these to the Irish situation and put forward a number of hypotheses. Using cross-section data from a ComReg survey of Irish-based SMEs, we then estimate a logit model of broadband adoption. Findings indicate that, among other factors, a company's industrial sector and other demand proxies are good predictors of broadband adoption. Controlling for other factors, regional market concentration appears to be negatively associated with the probability of broadband adoption. We propose that, in the absence of more detailed information, statistics on regional-level market structure could be a promising indicator of the supply-side.