Purpose: Timely supportive and palliative care (SPC) integration in adolescent and young adult (AYA) cancer management is recommended in curative and palliative settings. However, multiple barriers exist to implementing this goal. Liverpool Cancer Therapy Center (LCTC) serviced a growing AYA (15-39 years) population without AYA-dedicated services and the vast majority receiving no SPC engagement. Concerned this was placing AYA patients' wellbeing at risk, we determined a cultural change was required and that the newly established AYA Supportive and Palliative Care (AYASPC) Service could facilitate this. Methods: The AYASPC Service conducted a 6-month quality improvement project aiming to increase its referrals from a baseline average of one per month to four per month, to increase confidence in making SPC referrals and to enhance appreciation for specialized AYA care. Interventions included formalizing an AYASPC referral pathway with broad indications, and educating clinicians on holistic AYA care, the AYASPC Service's model of care (MoC) and AYASPC referral benefits. Results: During the project, 27 AYASPC referrals were made. Referrals consistently exceeded the Service's baseline, and from 3 months onward exceeded the project target. Additionally, referrals were made earlier (29.6% at diagnosis), for a variety of cancer diagnoses with varied prognoses, and for indications beyond traditional issues of complex symptoms and end-of-life care. Clinicians also expressed greater confidence in supporting AYAs and making SPC referrals. Conclusion: In a brief timeframe, the AYASPC Service's innovative and adaptable MoC and project interventions sustainably improved AYASPC access and affected a positive cultural shift around AYA care and advocacy.