Inter-Service Intelligence, (ISI) Pakistan
Established in 1948, Pakistan’s Directorate for Inter-Services Intelligence (ISI) is one of the most notorious secret service agencies in the world. Officially, the ISI is responsible for providing security intelligence assessment to the government of Pakistan; however, it is known to be involved in creating trouble in India. ISI is most known and famous agency among three agencies working in Pakistan; others are Intelligence Bureau (IB) and Military Intelligence (MI). ISI is known as command immense power in the Pakistani establishment, referred to principle brainpower organization of the country.
Central Intelligence Agency, (CIA) United States
If not the best, the Central Intelligence Agency (CIA) of the United States of America is indeed the largest secret service with the maximum reach. The CIA is known to play a pivotal role in helping the US maintain its status as the world’s sole super power. More importantly, CIA has been playing a central role in exchange of intelligence between countries to combat global terrorism.
Secret Intelligence Service, (MI6) United Kingdom
MI6 is known as the "the secret front line" of Britain`s national security, which is one of the oldest and was not acknowledged till 1994. The agency is tasked with gathering foreign intelligence from across the globe that could impact political and economic interests in the UK. MI6 has been closely involved in various conflicts in 20th and 21st centuries and keep close eye on internal and external terror activities, organizations and countries which could harm national defense and state security.
Federal Security Services, (FSB) Russia
Formed in 1995, the agency is committed to the country for intelligence, counter-terrorism and security enhancement and defense security. Previously known as KGB (at the time of USSR), has at least 250K personnel containing undercover agents, secret officers and foreign spies; it’s mainly fight the state crime, terror acts, drug smuggling and other internal security violence in the country.
Bundesnachrichtendienst, (BND) Germany
BND is Germany’s premiere intelligence agency that acts as an early warning system to alert the German government about threats to its interests. The main weapon in its armoury is electronic surveillance of international communications.
Research and Analysis Wing (RAW), India
RAW or Research and Analysis Wing was formed in 1968 and it’s the core Intelligence agency of India situated in New Delhi. The work of RAW includes data collection of neighboring countries and other specific countries that could influence the national interests of India. RAW has a major role in creation of the BanglaDesh and agency head reports only to Prime Minister (state head), not answerable to the Indian Parliament in any way as compared to other western intelligence agencies.
The Institute For Intelligence and Special Operation (MOSAD), Israel
MOSSAD is the intelligence agency of Israel. It began its operations in 1949. It is considered the 10th best intelligence agency in the world in 2015. The aim of this agency is to collect critical intelligence information and analyze it, perform secret operations in favor of national security and help fight the war on terrorism. Its main focus is on the Arab and Muslim countries. MOSSAD includes eight separate departments each performing completely solo from the other.
Direction Generale De La Securite Exterieure (DGSE), France
Why it is in top ten the answer is simple because it claimed that it has prevented 15 terror attacks in France; with a personnel of 5000 it works under the Safeguard Service of French Government. The General Directorate for External Security (DGSE) replaced the replacing the older Service de Documentation Extérieure et de Contre-Espionnage (SDECE) which has been formed in 1982.
Australian Secret Intelligence Service (ASIS), Australia
ASIS is Australia’s intelligence watchdog which keeps a close watch on developments across the world, especially in the Asia-Pacific region. Although Australia is relatively isolated from global terror, still ASIS works 24X7 to protect the country’s political and economic interests.
Ministry of State Security (MSS), China
The headquarters of MSS is located in Beijing. MSS is working closely with the security bureaus of the country in order to terminate any potential threats within the country as well. MSS of China is working in collaboration with ISIS of Pakistan in order to provide stability and prosperity in the South Asia region.