The emergence of an independent Ukraine is one of the most important geopolitical events resulting from the collapse of the Soviet Union. With a population of 52 million people, Ukraine is too populous and territorially too large and centrally located to be ignored. Its stability and prosperity have a direct bearing on regional security and more broadly, on European security. In an important sense, Ukraine is the cornerstone-the "keystone in the arch"-of the new European security architecture. This survey examines Ukraine's foreign and security policy since 1991. The first section focuses on the nexus between domestic and foreign policy. Subsequent sections analyze Ukraine's relations with Russia; ties to the United States and Europe, including the European Union and NATO; relations with Central and Eastern Europe; and Ukraine's role in the Baltic-Black Sea area. A final section examines Ukraine's future security options and their implications.