#398238. The official website of the British Secret Intelligence Service (SIS) The official website of the British Secret Intelligence Service (SIS), also known as MI6. It describes the work of SIS, its parliamentary, ministerial, judicial and financial oversight. It provides information on operational, adminstrative, technical and scientific careers in SIS, and the recruitment process. There is a section on the history of SIS and biographical information on some of its previous chiefs. Mi6.gov.uk~Site InfoWhoisTrace RouteRBL Check