He became Senator in the Ninth Congress from 1992 up to 1995. Paul Aquino, the brother of the late Senator Ninoy Aquino was the one who convinced him to run for office. He was again elected as Senator in 1998 and continues to serve his term up to this day. Currently, he is the Chairman of the Senate Committee on National Defense and Security and Committee on Urban Planning, Housing and Resettlement. Aside from this, he holds the following positions in the Senate: Vice-Chair of the Committees on Agriculture and Food and Foreign Relations, and a Member of 15 other Senate Committees. He is also the President of the Asian Regional Council Global Parliamentarians on Habitat, the Vice-President for Asia Global Parliamentarians on Habitat, the Co-chairperson of PLCPD and a member of the Commission on Appointments.