Senate Properties is a government owned enterprise and is responsible for managing the Finnish state's property assets and for letting premises. This paper reports findings of a case study of joint strategy creation in co-operation with Senate Properties and one of its key customers. The aim of the joint strategy creation is that Senate Properties could rent cost-effective and functioning workplaces to the key customer including all needed services. The joint strategy creation requires knowledge transfer on and between both strategic and operational levels to find a common understanding of the customer needs and service possibilities. Senate Properties has formed costumer teams controlled by customer managers to increase the knowledge transfer and develop the quality of customer service. The research is done as a social network analysis based on semi-structured interviews of the key participants in current service processes. All the key participants involved in service process from Senate Properties and the customer were identified and interviewed. The method was selected because of the need to understand the process of value creation and the channels of knowledge flow on and between strategic and operational levels through informal social network. The paper ends with a discussion on the need for further research on informal knowledge flows inside and between Senate Properties and customers on both strategic and operational levels. The need for analysis increases even more, when service providers will be linked to the service innovation processes.