Networks of firms have been in the focus of management research for several years. Recently, special attention has been paid to so-called business webs. Business webs are networks of firms which provide complements to a common product architecture. In the past, research focused on management issues of such webs but neglected the important question of how they actually came into being. The present book explicitly examines the formation and early growth of business webs. The author illustrates the early growth phases with two in-depth cases of the formation of the wireless internet ecosystem i-mode and the leading person-to-person online auction platform eBay. The book uncovers the contingencies under which the establishment of business webs is likely to succeed. Business researchers will benefit from the theoretical framework, while interested business managers will find explanations and advice for establishing a business web.