Martin Campbell-Kelly opened a new field in the history of computing in his groundbreaking From airline reservation to Sonic the Hedgehog; a history of the software industry. The book is discussed by Adrienne van den Bogaard and Frank Veraart and by Gerard Alberts, followed by a reply by the author. Van den Bogaard and Veraart join great appreciation for the three-sector division Campbell-Kelly developed to describe the history of the software industry, to a slight criticism of his ad hoc-argumentation in explaining why in each sector some enterprises survive and others do not. Lacking, in their view, is a discussion of the dynamics of software itself in the context of emerging practices and businesses. Alberts overcomes his prima facie unease with the