Educated in the Philippines, Marilu graduated Magna Cum Laude with a Bachelor of Science in Economics. She was admitted as an entrance scholar to law school and graduated from the University of the Philippines College of Law in 1980. Upon being called to the Philippine Bar in 1981 , Marilu joined a firm specializing in Banking and Corporate law, and subsequently served as in-house counsel for a major Bank. She continued to practice corporate law and held several positions simultaneously wherein she served as Vice-President and Chief Legal Counsel for several corporations in the Philippines. She also taught corporation law at the College of Law.

In 1981, Marilu established her own law practice, and has since represented numerous high profile cases in the lower court, as well as the Court of Appeals and the Supreme Court of the Philippines.

Marilu went on to post graduate studies at the the University of California at Los Angeles (UCLA) where she specialized in immigration law, and subsequently practiced law in Beverly Hills, California, U.S.A.

Mendoza-Arzaga-Mendoza Law Firm is pleased to announce that Pace Law Firm in Toronto, Canada will act as their Canadian Legal Counsel specific to all Canadian immigration applications.