Turkmenistan is a country located in Central Asia bordering the Caspian Sea. Neighboring countries include Afghanistan, Iran, Kazakhstan, and Uzbekistan. The geography of Turkmenistan largely consists of the Karakum Desert and mountains in the southern region. Turkmenistan defines the government system as a secular democracy and a presidential republic, but in actuality the country displays authoritarian presidential rule, with power concentrated within the presidential administration. The chief of state and head of government is the president. Turkmenistan has a planned economy due to government control of most of the economy, although there is limited private sector development.