By empirically surveying over 200 responding firms, the study found that network externalities greatly affected adopting firms' willingness to stay in existing or current e-marketplaces and/or to switch to another one, but both network externalities and transition costs are not antecedents of firm-level technology adoption. Also, transition costs did not play an influential role on enterprise e-marketplace adoption at the post-decision stage. The empirical evidence also verified that TAM effectively forecasts enterprise e-marketplace adoption, and selling technology-based new products to firm-level customers with a higher push from the external environment is more effective than that with a higher push from the internal environment of the firm. Findings derived from this empirical survey may pave the theoretical ground for a better understanding of how a general technology is adopted by business firms.