The Bill to establish the Office on Missing Persons (OMP) was presented in Parliament on 22 June 2016 and the Office on Missing Persons (Establishment, Administration, and Discharge of Functions) Act, No. 14 of 2016 (OMP Act) was passed in Parliament on 11 August 2016. On 28 February 2018, seven commissioners and a chairperson were appointed based on the recommendations of the Constitutional Council.

The establishment of the OMP marks a significant milestone in the efforts of the Government of Sri Lanka to address the issues of the missing and disappeared. Successive governments set out measures to investigate disappearances, including through appointing commissions of inquiry or ad-hoc mechanisms with limited mandates. While making critical contributions in the way of recommendations, these previous mechanisms were unable to provide answers to the many thousands of families searching for their loved ones.

As a permanent and independent state institution, the OMP is responsible for clarifying the fate and whereabouts of persons who went missing or disappeared in connection with the conflict, political unrest, or civil disturbances, or as a result of enforced disappearances.