oo small or the technologies they need have nonstandard software interfaces, the vertical software industry evolution may freeze to the second phase, although the number of software P. Tyrväinen Department of Computer Science & IS, University of Jyväskylä, P.O. Box 35, 40014, Jyväskylä, Finland e-mail: Pasi.Tyrvainen@jyu.fr P. Tyrväinen and O. Mazhelis (eds.), Vertical Software Industry Evolution, Contributions to Management Science, DOI 10.1007/978-3-7908-2352-3_17 C Springer-Verlag Berlin Heidelberg 2009 P. Tyrväinen companies is decreasing in some market segments implying that the market has reached a mature stage in the industry evolution model. This means that the software development activity is redirected, to some extent, to some other indus- tries although no productized solutions have been fully adopted. This also is an opportunity for service providers to offer alternative approaches to the operators, such as business process outsourcing as a mean to gain some cost advantage although not comparable to automating the processes with software. This book describes the 2-year research effort to analyze the vertical software industry of telecom operator software, that is, the OSS/BSS software. After the theory background in Part I, Part II used multiple means to analyze the current status of the industry. The results imply that only the very largest operators still develop software in-house as a means to gain competitive advantage. However, only a small percentage of their software spending goes to software products while a large volume of effort is still directed to external software consultancy based on customer-defined specifications as well as tailoring based on core software product from an independent software vendor. (The reasons for these are elaborated in the next subsection.) There exists also some variation between different geographical regions as well as between different market segments within the same market. In practice, the difference between market segments means that small operators have to