In December 2007 the Dutch government agreed on the action plan Netherlands Open in Connection, hereafter called NOiV, the Dutch acronym. The objectives of this strategic plan are the following: 1. increase interoperability by accelerating the use of open standards; 2. reduction of supplier dependence through a faster introduction of open source software, open standards and the use of ODF (a document format based on an open standard); 3. promotion of a level playing field in the software market (.) by forceful stimulation of the use of open source software, and by giving preference to open source software during the process of IT acquisition. To reach these goals the action plan describes a number of different policies for open standards and open source software. A vast number of these policies directly affects the process of IT procurement within government organisations. To understand why some objectives are supported and some are resisted by government buyers, the following researchquestion was selected: How and under what circumstances does a strategic IT plan influence behaviour regarding the practice of public tenders? If these circumstances can be identified it would become possible for policymakers to take them into account while designing future strategic IT policies. To answer the research question a conformance and performance research methodology is used. This methodology focuses bottom-up on the influence a strategic policy has on the behaviour of a targeted organisation during the policy implementation phase. A strategic policy is fulfilling its purpose if it plays a tangible role in the choices of the addressed policy takers. Through monitoring information is produced about the observed policy outcomes (conformance) and through evaluation the research produces information about the value of the observed policy outcomes (performance). To see how the Dutch strategic IT policy is enacted in practice, empirical quantitative research was carried out which asked for the data of all the Dutch calls for ...