This research is based on a new law relating quality assurance in construction that was proposed in 2016. The main aim of the legislative proposal is to improve the quality of construction by privatising the way of assessing quality on the basis of the Building Decree. The problem is that the contractor gets more responsibility in this process through the new law. Since the change in the way of quality assurance asks for a new way of working from contractors the contractors have to adapt their organisations towards this change in responsibility. The changes can be distinguished on a legal implementation and organisational implementation level. This research focuses on the social scientific perspective of this law; being the organisational implementation. Within this organisational implementation, the focus of this research is the organisational culture and structure. The research question is therefore: How can a contractor change its culture and organisational structure, to adopt a pro-active attitude in quality assurance? The research strategy is to perform qualitative research. For this research, the method to be used is doing literature research. The literature research reviews the change based on a why-how-what structure. This literature research results in multiple findings on different subjects. Findings which form the basis of an advice on how to approach an organisational culture and organisational structure change. To validate these findings and the advice, both are submitted to a validation process. The deliverable at the end of the research is the advice for the contractors on how to adapt their organisational culture and organisational structure, which will be reflected in an advice brochure. The conclusions of this research start by describing that current organisations of contractors miss a branch or layer on quality management. To change this, a power strategy or planned strategy should be chosen with unilateral implementation instruments. The change process should, regardless the chosen strategy, be implemented on different levels, which was found to reduce resistance for change. The process of change should be started within a project in which the client is interested in improving quality assessment as well. It is concluded that a manager who stands behind the changes and is committed to those change, should be made in the lead of implementing the strategy within that project.