The Shanghai State Security Bureau (SSSB; Chinese: 上海市国家安全局) is a municipal bureau of China's Ministry of State Security (MSS) charged with intelligence operations in the country's most populous city. With tens of thousands of employees, it is one of the most aggressive and internationally active units of the MSS, conducting long-term global foreign espionage operations and major cyberespionage campaigns which stretch far beyond the Shanghai metropolis. The bureau acts in concert with the Shanghai Municipal Party Secrecy Committee, and the two represent themselves publicly as one institution, a front called the Shanghai Secrecy Administration Bureau (SSAB, Chinese: 上海市国家保密局).
