Maize (Zea mays L.) is a diploid (2n=20) belonging to the tribe maydeae of the Gramineae family. It is believed that the crop was originated in Mexico and introduced to WestAfrica in the early 1500s by the Portuguese traders. It was brought to Ethiopia in the 1600s to 1700s. Currently it is grown over a wide range of environmental conditions through out the world .Seed is a means of dispersal for plant populations,representing continuity and change, and thus adaptation to the local environment. In modern agriculture,seed is a vehicle to deliver almost all agriculture-based technological innovations to farmers so that they can exploit the genetic potential of new varieties.The assessment of formal and informal seed systems of maize is important not only to identify the potentials for future investments on seed sector but also to encourage the existing institutions for quality seed production and supply. This book indicates opportunities of maize seed system and helps the public and private institutions which need to involve in seed production.