The name Omo-Naaddaa is derived from Omo and Naaddaa Rivers, which flow in the area. Omo-Naaddaa''s natural endowment has constantly attracted different groups of peoples i.e. Gaaroo, Oromo, Yam, Kafichoo, Daawuroo, Hadiyyaa etc. Continual migration with natural increase and state policy interventions led to escalating crop production, which in turn has been responsible to environmental changes. For the Oromo, Omo-Naaddaa has been known to be the centre of various historical processes. Odaa Hulle that served as gadaa confederacy centre is situated in Omo-Naaddaa. Daakkaanoo, which was Jimmaa Kingdom''s iron mining centre, is located there. The area was also known as strategic station for local, middle and long distance trade passing along the axis of southwest to northeast. This book depicts demographic settlement pattern, land use, crop types, agricultural practices and physical landscape transformations of Omo-Naaddaa. It narrates consequences of agricultural expansion on the surrounding non-farm lands and effects of urbanization on agricultural hinterlands.