Increasing collaborative working between GPs and community pharmacists has recently become a high priority for the NHS. Previous research suggests that interaction is limited and problematic between the two professions, forming a barrier to service provision. This PhD aimed to explore the level, nature and process of interaction between GPs and community pharmacists, using a social network analysis approach.The study focused on four geographically different case study areas and 90 GPs and community pharmacists participated in total. A two-stage design was adopted. Firstly data were collected through a network questionnaire and analysed using social network analysis. Secondly, qualitative interviews were conducted to provide narrative to the network findings and analysed using the framework approach.The nature of contact was characterised as mostly indirect through brokers, de-personalised and non-reciprocal and seemingly at odds with collaborative behaviour. A misalignment in responses pointed to asymmetry in the relationship, representing little commonality, knowing and understanding of each other. Through social network analysis, individuals and dyads in possession of strong ties were identified. Strong ties were not the norm and were characterised by more personalised forms of reciprocal contact. Qualitative interviews provided insight into the processes of interaction between the two professional groups. An approach to the interaction, which involved pharmacists tactically managing the potential conflict in the interaction through use of deferential and sometimes subservient behaviour, was conceptualised as the 'pharmacist-GP game'. Those pharmacists with strong ties to GPs also, at times, adopted aspects of this approach but also attempted to set themselves apart from other pharmacists in order to develop and maintain their strong ties with GPs. However, possession of strong ties did not always lead to capitalisation, and the benefits of possessing these were often viewed as efficiency and convenience gains rather than anything more wide-reaching. Often, more isolated GPs and pharmacists did not view strong ties as a necessity, with the benefits of these not considered rewarding enough for the time and effort required to achieve them. This effort-reward conflict was identified as an important constraint faced by GPs and pharmacists in relation to transforming these loose connections into more integrated networks. Other micro and macro level constraints were also identified and a series of accompanying recommendations made for future practice and research.