The first measles vaccination was introduced in 1963, then improved in 1968. During the years 1967 and 1968, a mumps and rubella vaccination was also introduced . The three vaccines were combined in 1971 and called the measles-mumps-rubella (MMR) vaccine (Immunization Action Coalition, “Measles: Questions and Answers”). One dose of MMR vaccine has been shown to protect approximately 90-95% of children, then in 1989 the Centers for Disease Control and Prevention (CDC) and the Prevention Advisory Committee on Immunization Practices decided to change the dose from one to two, increasing the dose. The percentage of protected children amounts to approximately 97% (National Network for Vaccination Information (NNii), “Measles, Mumps, Rubella (MMR)”). The CDC reported that 95% of children who receive the first dose of MMR vaccine between the ages of 12 and 15 months become immune to measles, mumps, and rubella after this initial dose. Those who do not become immune after the first dose become immune after the second dose administered between the ages of four and six (Centers for Disease Control and Prevention, “Vaccines”). Thanks to these changes, measles, mumps, and rubella have been nearly eradicated in the United States. However, to ensure that these diseases do not spread from countries that do not carry out vaccinations, it is important to continue our current programme. Although MMR vaccination is the safest way to ensure that an epidemic does not occur, vaccination has been a source of controversy over the years. The MMR vaccine was once thought to be unsafe because it not only overwhelmed the immune system, but also contained toxic additives and was thought to be linked to autism. Since then the studies have pro...... half of the paper ...... two took fourteen days and had sixteen experts, five for families and eleven for government. In 2010, after an eight-year court trial in the United States Federal Vaccine Compensation Court concluded that MMR vaccination did not cause autism in the six test cases reviewed by the court. Both theory one and theory two were found to be implausible (Kirkland, 237-261). Studies conducted over the years alongside the Special Tribunal on Vaccine Injury have all agreed that there is no evidence linking autism and MMR vaccination. Studies also show that 95% of children who receive the first dose of the MMR vaccine between 12 and 15 months develop immunity to all three viruses. A second dose is given between ages four and six; this second dose gives immunity to almost all those who did not respond to the first dose.