Mr. Alfonso is a lecturer at the San Sebastian College of Law, where he teaches courses on Criminal Law. He is also a Bar Examination Coach for Criminal Law at the San Beda University Bar Review Center.

He is a Trained Arbitrator at the Philippine Dispute Resolution Center. He is also a member of the Young Singapore International Arbitration Centre Group.

Mr. Alfonso was admitted to the Philippine Bar in 2017 and is a member of the Makati City Chapter of the Integrated Bar of the Philippines.