This is the fifth article in the psychological elements of palliative care series. This series focuses on how key concepts from psychotherapy can be used in the context of palliative care to improve communication and fine tune palliative care interventions. In this article, we discuss attachment-the system by which people form bonds in relationships. The different styles that people have in navigating relationships such as clinician-patient relationships develop from early life onward. Attachment styles are not pathological. But they are helpful to understand because they are a relatively stable factor that impacts how people relate to caregivers like clinicians. Our patients all express unique relational needs to us; some of our patients need closeness and reassurance to feel comfortable, others value independence and space. These needs are highly significant to palliative care clinicians; they inflect our patients' goals of care and values, they modulate our patients' psychosocial needs, and they elucidate the ways our patients respond to a range of therapeutic interventions. Understanding attachment gives us a window into these individual care needs and empowers us to tailor the care we provide for a wide range of patients.