This book describes an exploratory research into the influence of different contract types on the effectiveness of owner-contractor working relationships in construction projects, which has a major effect on the project performance. This study is an example how Q-methodology can be used and operationalized to support socio-technical qualitative research. Applying Q-sort survey, subjective opinions and reflections of the project managers from owner and construction firms involved in 4 construction projects on the relative influence of various contract types and of other influencing factors were systematically analysed. On the basis of Q-factor analysis, three distinct perspectives were revealed, namely a) strong leadership and management, b) effective team integration, c) strong capabilities and structure. Across these perspectives, the project managers shared a believe that contract type does not have considerable influence on the owner-contractor relationship effectiveness.