Since 2012, Dennis has supported healthcare transformation through leadership development, partnering with SingHealth to co-design and implement programmes like SLP (122 runs), TLP (75 runs), and OLP (23 runs), also coaching leaders across various levels. He facilitates strategic planning with leadership teams and currently designs leadership development for nursing leaders at NUHS. Formerly Honorary Secretary and Vice-President of the Asia Pacific Alliance of Coaches, he led regional coaching initiatives. Beyond healthcare, he coached marginalized communities and led resilience programmes in the Philippines post-Typhoon Yolanda. He now conducts TRE sessions for stroke patients in the RISE Community in Yishun.