Service Delivery Networks (SDN) have not been widely considered in complex service environments such as healthcare. There is reported concern for service network functioning of Care Programme Approach (CPA) Case Management in UK Mental Health and Learning Disability services. In this study we adapted the concept of the SDN for an exploratory investigation of a series of CPA case reviews in a Learning Disability Service. Based on a template analysis, we described a SDN at the intersection of patient, commissioner and clinician network participation. From this vantage point we elicited a marked variation in SDN participation quality, giving rise to suggestions for service improvement and further research.