The most promment distinguisbing characteristics of maize-growing reglons in developing countries are given here in tabular form, along with sallent features of each region. Eaeh region is designated by a number, which appears as a column head in the table and is aiso recorded on the accompanying map. Major cities and selected experiment stations are indicated on each country map. Area of maize cultivated in the regions is expressed in 1000s of hectares. Many regions under 20,000 hectares are not included. The region hectarages should he considered as best estimates and thus serve as a good guide for priority setting in breeding projects.