Network externalities.

A previous entry (Competitive Market Theory) outlined the traditional economic model for the 'Old World' which was driven by economies of scale and scope. The 'New World', characterised by information and communications technology is governed by a different dynamic. Network externalities are the new drivers of the network economy (see Networks; & Network Industries). It is important to recognise that economies of scale/scope and network externalities represent the extreme ends of a spectrum of effects, and that the presence of one does not imply the exclusion of the other. [ABSTRACT FROM AUTHOR]