In May 2024, he was elected Chair of the Senate Committee on Trade, Commerce, and Entrepreneurship and Chair of the Senate Committee on Higher, Technical, and Vocational Education.

Senator of the Philippines:

• filed the "Konektadong Pinoy Act" to upgrade telecom infrastructure, lauded Alas Pilipinas women's volleyball team for historic AVC Challenger Cup bronze and led Senate to honor men's and women's teams for SEA Volleyball League bronzes, aided 800 beneficiaries in Apayao and Cagayan, pushed for BCDA role enhancement and DepEd school rehab funding restoration; school rehab funding restoration.
• He became Senate minority leader in September, chaired banks, financial institutions, currencies and justice, human rights committees, filed bills to abolish travel tax, establish sports department, reform education subsidy, expand barangay healthcare, set up 24/7 super health centers, formalize barangay health workers' employment and expand kasambahays' rights, sought Duterte's house arrest, criticized flood control corruption probe delay and DPWH fund waste, withdrew Commission on Appointments nomination to break deadlock, and saw five higher education measures he backed enacted into law.

Completed his term in the House, focusing on local and national legislation related to pandemic response and economic recovery. Left the Nationalist Party in 2021 and became an independent.

• Continued as Taguig-Pateros rep, focusing on pandemic relief and livelihood support for constituents.

Resigned from the Senate on May 17, 2017, to assume the role of the 26th Secretary of Foreign Affairs under the Duterte administration. Served until October 17, 2018.

• In August, he attended his first major regional meeting as foreign secretary, the 50th ASEAN Foreign Ministers Meeting, where he participated in negotiations on the joint communiqué regarding the South China Sea and North Korea's nuclear program, but skipped the second day due to illness.
• In February, during the ASEAN Foreign Ministers' Retreat in Singapore, he held a town hall meeting with Filipino community leaders to update them on government services for overseas Filipino workers and address their consular and labor concerns. In Augus he paid a courtesy call on ASEAN Secretary-General Dato Lim Jock Hoi at the ASEAN Secretariat. He stepped down from his post as Secretary of Foreign Affairs in October to prepare for his run for Taguig-Pateros congressman in 2019.

Senator of the Philippines: Elected Senate Majority Leader (preceded by Gregorio Honasan, acting). Chaired the Senate Committee on Rules.

• Filed bills including the Freedom of Information Act, Orphaned Children’s Welfare and Protection Act, Iskolar ng Bayan Act, and measures to increase teachers’ compensation and decriminalize libel.
• Continued leading the Senate majority, advancing legislative work on education, social welfare, and governance. Pushed for initiatives to improve public services and strengthen accountability mechanisms.
• Received the Gawad Dangal ng Lipi Award for exemplary public service from the Provincial Government of Bulacan. Remained active in advocating for pro-people policies, laying groundwork for his 2016 vice presidential campaign.

Elected to the Senate. Served as Chair of the Senate Blue Ribbon Committee.

• Continued criticizing the Arroyo administration, leading investigations into the NBN-ZTE deal, fertilizer fund scam, and Malacañang cash-giving scandal. Filed the Freedom of Information (FOI) Act, which passed the Senate on third reading in the 14th Congress.
• Spearheaded the passage of Republic Act (RA) 9500, the University of the Philippines Charter Act, expanding UP's mandate and autonomy. Pushed for improved educational loans, scholarships, funding for basic and tertiary education, and better compensation for public school teachers. Co-authored RA 9521, the National Book Development Trust Fund Act, to support the book industry.
• Authored or co-authored several key laws: RA 9647 (Anti-Cam cording Act), RA 10122 (Act Strengthening the Literacy Coordinating Council), RA 10152 (Mandatory Basic Immunization Services Against Hepatitis-B for Infants Act), and RA 9994 (Expanded Senior Citizens Act). Stepped down as Blue Ribbon

Served as Deputy Majority Leader and Vice Chairman of the House Committee on Rules. Switched to the Lakas-CMD party.

• Co-authored the Anti-Money Laundering Act of 2001 to strengthen financial oversight and combat illicit financial activities.
• Focused on legislative work for overseas Filipinos, co-authoring the Overseas Absentee Voting Act of 2003 to enable Filipinos abroad to exercise their right to vote. Pushed for measures to improve local infrastructure, education, and healthcare in his constituency.

Elected in 1995, though his official proclamation was delayed until 1998 (10 days before his term ended).

• In his short tenure, he pushed for better waste management systems and expanded healthcare access for indigent families.
• Coordinated with local officials to streamline permit processing for small businesses, supporting local economic activity.