Military service is service by an individual or group in an army or other militia, whether as a chosen job or as a result of an involuntary draft (conscription). Some nations (e.g., Mexico) require a specific amount of military service from every citizen (except for special cases, such as physical or mental disorders or religious beliefs, and most countries that have conscription only conscript men). A nation with a fully volunteer military does not normally require mandatory military service from its citizens, unless it is faced with a recruitment crisis during a time of war.
In this summary, 195 countries are included.
The following nineteen countries have been identified as having no defence forces or as having no standing army but having very limited military forces:
The following 105 countries have been identified as having no enforced conscription:
The following ten countries and colonies have been identified as having both compulsory and voluntary military service:
The following 13 countries have been identified as having selective conscription:
The following thirteen countries have been identified as having a civilian, unarmed or non-combatant service optional alternative to compulsory military service:
The following twenty-one countries have been identified as having compulsory military service limited to 1 year or less:
The following 8 countries have been identified to having compulsory military service limited to 18 months or less:
The following thirty-two countries have been identified as having compulsory military service terms longer than 18 months:
As of 2015[update], three countries have been identified as intending to abolish conscription in the near future:
Compulsory military service has declined considerably since 1970. A 2016 study finds "that the probability of a shorter military service time is positively associated with smaller country populations, smaller lagged army sizes, increases in primary schooling among young males, and having common law legal origins."
Albania had compulsory military service. Albania's armed forces announced an objective to create a professional army by the end of 2010.
Argentina suspended military conscription in 1995 and replaced it with a voluntary military service, yet those already in service had to finish their time in service.