The most significant threat to national security in the twenty-first century is terrorism. The ‘smart approach’ to counter terrorism is a blend of both hard and soft approaches. Governments now adopt a whole of nation strategy to counter terrorist recruitment and deradicalise inmates and detainees. Rehabilitation is considered a global imperative, in the battle against terrorism. Rehabilitation programs must be designed to deradicalise inmates and detainees, a process that goes beyond disengagement. Sri Lanka’s rehabilitation program to reverse the process of radicalisation contained six components targeted at bringing the beneficiary back to mainstream, plus one community component to ensure that treatment gains are sustained once reintegrated into community. The challenges are many for the beneficiary that returns to the community, with terrorist networks attempting to re-radicalise the reintegrated. Therefore to sustain the changes and maintain beneficiaries within the mainstream, community engagement and reconciliation becomes a necessity. Rehabilitation is not a one-off intervention, and deradicalisation is not an all-or-none state. Civilians groomed into terrorism are vulnerable citizens, and upon reintegration, requires ongoing engagement. The risks posed by weak governments that undermine security can damage the rehabilitation process and heighten the risk of re-radicalisation.