This paper identifies and discusses important political and economic aspects of Turkish accession to the EU. Under the present rules, Turkey’s size would give it the greatest number of votes within twenty years and its low income and dependence on agriculture the largest net transfer from other members. Free labor mobility would lead to substantial migration to the present EU; the Turkish immigrant population in Germany may increase from 2 to 3.6 million in thirty years. Most of the economic effects will be felt by Turkey, particularly in agriculture. The main obstacles to accession are not economic, but political, however. Historical experience makes it difficult for Turkey to eliminate the decisive political role of the military, to give Kurds and other minorities cultural rights and uphold basic human rights; these issues are perceived to threaten national unity and territorial integrity. Turkish membership is resisted by many in the EU because Turkey is not considered to be part of Europe geographically and culturally.