In this chapter we will outline a rationale for formulating with carers. We will present the evidence to support developing shared formulations and describe a clinical approach to achieve this, which will be illustrated with a case example to demonstrate its practical application. The case example focuses on a range of issues that are present in working in many different settings, but here we specifically focus on developing shared formulations with professional caregivers working with an inpatient with a diagnosis of psychosis. Many of the themes are also applicable when working with informal carers such as family members and with other client groups, and we draw on this literature where relevant. We define carers as both professional and informal caregivers who have accepted or been given the role of supporting a person or people with mental health needs.