Eritrea is a country in Eastern Africa bordering Djibouti, Ethiopia, Sudan, and the Red Sea. Eritrea has a strategic location along the world's busiest shipping lanes. The country is bisected by mountain ranges, formed by the processes that formed the Great Rift Valley, with fertile lands to the west descending to desert in the east. The government system is a transitional government. The chief of state and head of government is the president. Eritrea has a command economy in which the central government, controlled by a single political party, directs the economy regarding the production and distribution of goods. Eritrea is a member of the Common Market for Eastern and Southern Africa (COMESA).