INTRODUCTION Adolescents and young adults aged 15-39 years who have been diagnosed with cancer (AYAC) have unique medical and psychosocial needs. Following their cancer treatments, AYAC must learn to manage the sometimes irreversible general side effects of cancer treatments including side effects that impact their sexuality. These side effects include but are not limited to: infertility, altered body/physical appearance, and sexual dysfunction. Such effects may hinder AYAC efforts to date and experiment sexually, limiting sexual maturation and confidence, as well as the formation or maintenance of meaningful couple and sexual relationships. It is clear that we need to tailor our clinical approaches to ensure that we assess the unique needs and concerns faced by AYAC. AIMS Based on consistent study findings substantiating the distinctive needs of AYAC, the main objective of this article is to present the core clinical components involved in assessing sexuality among AYAC. METHODS The clinical recommendations are based on the authors and experts' clinical experiences coupled with a thorough examination of the literature related to AYAC sexuality. MAIN OUTCOME MEASURES This article first describes the three components (clinical interview, review of chart notes, and self-report questionnaires) of a sexuality assessment and the seven core domains that highlight target areas of focus. RESULTS A detailed outline of each of the core domains of assessment (socio-demographics; medical history; fertility and sexually transmitted infection; sexual functioning; sexual coping style; body and self-image; and sexual history and dating/couple experience) is presented. A "toolbox" table containing useful resources for clinicians (e.g., questionnaires and red flags) and direct resources for AYAC patients are included. CONCLUSION Cancer can have a significant impact on numerous domains of AYAC sexuality. The assessment of and attention to the impact of sexuality on AYAC is crucial in order to provide effective and comprehensive quality patient cancer care.