Measles, Mumps, and Rubella (MMR) vaccination is crucial for preventing these highly contagious diseases, which can lead to serious complications such as hearing loss, fertility problems, and congenital defects. Screening involves checking vaccine records or laboratory evidence (serology) to confirm immunity, particularly important for healthcare workers, college students, and women of childbearing age. Testing helps confirm current or past infection and verify whether vaccination is needed. The recommended vaccination schedule typically includes two doses in childhood at 12–15 months and 4–6 years, with additional doses or testing for high-risk groups and those lacking immunity documentation. While generally safe, the vaccine is contraindicated in certain situations (e.g., pregnancy, severe immunocompromise), and mild side effects—like fever or rash—may occur. Always consult the most recent CDC guidelines and a healthcare provider for personalized advice.