Simons began his journalistic career in 1964 as a reporter for the Associated Press. Specialized in Asia affairs, he has reported extensively on war, civil unrest, politics, and economics, visiting Pakistan, Afghanistan, Japan, South Korea, Malaysia, Singapore, Vietnam, Philippines. In 1971, he joined the Washington Post and served as a correspondent in India and Thailand next few years. Since 1982, Simone has worked as a correspondent for the Mercury News based in Tokyo. One of his projects during this period was a series of articles with correspondents Pete Carey and Catherine Ellison on the massive transfers of wealth abroad by the President of the Philippines Ferdinand Marcos and his associates. Being on Tokyo assignment in 1985, Simons was investigating the circumstances of the death of the politician Benigno Aquino, when he came across the information about Marcos' financial affairs. In 1986, three correspondents were awarded the Pulitzer Prize for International Reporting. A year after, Lewis Simons published a book on the Philippine revolution "Worth Dying for".