A growing evidence base highlights the negative impact of poor psychosocial care at end-of-life. Adolescents and young adults (AYAs) 15-39 years of age with cancer face unique medical and psychosocial challenges that make them especially vulnerable when treatment is not successful. Although the importance of age-appropriate medical and psychosocial care is internationally recognized for AYAs across the cancer trajectory, there is little guidance on best-practice care and communication practices with AYAs as they approach the end-of-life. We conducted a narrative review and found evidence points to the potential benefits of introducing palliative care teams early in the care trajectory. Research undertaken to date emphasizes the importance of exploring AYAs' preferences around end-of-life issues in a repeated, consistent manner, and highlighted that AYAs may have strong preferences on a range of issues such as being able to stay in their own home, being comfortable and free from pain, and expressing their wishes to loved ones. We highlight a number of best-practice recommendations to guide clinicians around the critical elements of when, who, what, and how end-of-life conversations may be best facilitated with AYAs. Gaps in the evidence base remain, including research focusing on better understanding barriers and facilitators to timely, age-appropriate end-of-life communication for AYAs with different diagnoses, where discordance between AYA-parent preferences exists, and when AYAs die at home versus in hospital. We have proposed a new model to support clinicians and researchers to better conceptualize how interacting individual, familial, and sociocultural factors impact end-of-life communication with AYAs in clinical settings.