Greater Angkor was the capital of the Khmer Empire from the ninth to the fourteenth centuries a.d. The rulers of Angkor left behind magnificent temples, along with extensive, centrally planned landscapes and massive urban complexes. However, the landscape of Greater Angkor also represents a decentralized planning tradition. This article addresses the different scales of economic landscapes at Greater Angkor: from massive rice-field superstructures watered by artificial irrigation, to smaller patches of fields organized around local temples and ponds. Contrary to widely accepted views, the design of extensive cultural landscapes does not require the presence of an elite controlling authority, or the guidance of a commonly conceived plan. Within Greater Angkor, the design of extensive landscapes often occurred at the local level, most likely involving local traditions rather than abstract, centrally approved plans. The relationship between centralized and decentralized planning traditions is investigated using a topographic classification of the landscape based on extensive mapping from remote sensed imagery from 2007–2010. Covering 1000 km2 of rice fields, and including 22,000 km of rice-field bunds, the topographic classification of the rice-field systems reveals two very different ways of building. These two systems are best described as coaxial systems and cardinal systems: both suggest dramatically different development models and socioeconomic frameworks. The two different, and extensive, development processes had a lasting physical impact on the resulting landscapes, and are still actively used today. This article discusses the evidence for both central and local plans as well as more complicated examples, where both central and local plans seem to have influenced the design of landscapes. Illustrated examples of centrally planned landscapes and local approaches to planning landscapes demonstrate this premise.