Here are some links for additional resources to help you with your understanding of Home Team agencies and related organizations.

MHA and Home Team Agencies
Singapore Police Force
Internal Security Department
Singapore Civil Defence Force
Immigrations and Checkpoints Authority
Singapore Prison Service
Central Narcotics Bureau
Home Team Academy
Gambling Regulatory Authority
Yellow Ribbon Singapore
Other Agencies
AETOS Security Managment
Attorney General’s Chambers
Certis CISCO
Corrupt Practices Investigation Bureau
National Police Cadet Corps
Voluntary Special Constabulary