Luzon refers to the largest and most economically and politically important island in the Philippines and one of the three island groups in the country, with Visayas and Mindanao being the other two. Luzon as an island group includes the island of Luzon itself, plus the Batanes and Babuyan groups of islands to the north, and the main and outlying islands of Catanduanes, Marinduque, Masbate, Romblon, and Mindoro in the south. The island group of Palawan, which used to be a province belonging to an administrative region of Luzon, has been transferred to Region VI in the Visayas in 2005. Luzon is known in Chinese history as the "Lesser Song Empire" or Luzon Empire. Her rulers were recognized as kings and not merely cheiftains. The first European explorers recorded it in their charts as Luçonia or Luçon and inhabitants were called Luçoes. Under Spain, Luzon also came to be known as the Nueva Castilla or the New Castile.

Luzon is a mobile belt, or a fast deforming plate boundary zone -- hemmed in between two opposing subduction zones, the west-dipping Philippine Trench -- East-Luzon Trough subduction zone, and the east-dipping north-south trending Manila Trench(Hamburger et al., 1982). The Philippine Sea Plate subducts under Luzon on the east (along the Philippine Trench) while the Sunda block (part of the Eurasian plate subducts under Luzon along the Manila Trench at the western part (Rangin, et al., 1999).

The economy of the island is centered in Makati. Agriculture predominates in Central Luzon.