As Defence Cyber Chief since Jan 2025, and concurrently Commander Defence Cyber Command since Mar 2025, COL Clarence Cai oversees the cyber defence operations, capability development and strategy of the Singapore Armed Forces (SAF). He has held appointments in Cyber Staff since 2020, where he formulated plans for the SAF’s cyber force development.

COL Cai has served in various command and staff appointments in the SAF, including Commander, Second Singapore Infantry Brigade. In 2010, he served as Executive Officer to the Head of Operations for Regional Command (South) in Kandahar, Afghanistan as part of the International Security Assistance Force (ISAF) with the US 10th Mountain Division. He is a graduate of the Indonesian Command and Staff College (SESKOAD).

COL Cai was a Mason Fellow at the Harvard Kennedy School of Government in 2018, and a Schmidt Futures International Strategy Forum 2023 Asia Fellow. He graduated Magna cum Laude from Harvard University in 2004. COL Cai holds the "Exploit Researcher and Advanced Penetration Tester" (GXPN) and Global Industrial Cyber Security Professional (GICSP) certifications.