oject and the book are: What is the current state of the CSP software market evolution? Does this market vertical comply with the findings about other software market verticals? How and when will horizontalisation emerge in this vertical software market? What strategies do the software vendors follow in this vertical? Will vertical integration strategies of systems (including software) and vertical industry software solutions emerge? Or will the market rather be dominated by commodity hardware and software? What will be the role of service oriented architectures in this market? Is it considered by the related enterprises as a market segment or as a technical platform with potential micro ecology / IPR protection strategies? Do software component markets evolve from service oriented architectures to service delivery platforms? How to support telecom operators on "make or buy?" decisions by estimating development of specific market segments? The distilled outcome of the research describes expected future scenarios for the vertical software market, and critical factors impacting the business and competi- tive positions. P. Tyrväinen and M. Pulkkinen 3 Data Sources Used One of the challenges in analysing an emerging or an evolving market is the availability of sufficient and reliable data. In this book a wide variety of heteroge- neous data sources are used, varying from public and commercial market research reports and databases to interviews with domain experts. Both qualitative and quantitative data are employed. Different sources of data were often required when analyzing the vertical software market from the viewpoint of telecom pro- cesses, markets, and related technologies. One of the main sources of quantitative data used in the book is a commercial data set (coined OSS/BSS KnowledgeBase) acquired from Dittberner Associates (www. dittberner.com), an international market research and consulting firm with focus on the telecommunications industry. It offers surveys and related data on the OSS/BSS industry develo