The 2007 CIA World Factbook

by United States. Central Intelligence Agency

Mauritania
18 years of age; universal

Mauritius
18 years of age; universal

Mayotte
18 years of age; universal

Mexico
18 years of age; universal and compulsory (but not enforced)

Micronesia, Federated States of
18 years of age; universal

Moldova
18 years of age; universal

Monaco
18 years of age; universal

Mongolia
18 years of age; universal

Montenegro
18 years of age; universal

Montserrat
18 years of age; universal