The United States Department of State is responsible for the country's foreign policy and diplomatic relations with other nations. There are several synonyms for this department, including State Department, DOS, Department of Foreign Affairs, and Department of International Relations. Each of these terms refers to the same government agency and its various offices and bureaus. The United States Department of State is a crucial institution that works to promote and protect the interests of the United States abroad. Its activities include everything from negotiating treaties to providing assistance to American citizens traveling or working in other countries.