Determining whether, and when, to get one's children vaccinated has become an increasingly controversial decision, often leaving parents fearful of making the “wrong” choice. Part of the challenge stems from the fact that what is rationally optimal for an individual is inherently at odds with the best outcome for the community, meaning that if everyone acted out of self-interest with respect to pediatric vaccines, communal health would suffer significantly. Given these tensions, the issue of pediatric vaccines benefits greatly from the nuanced assessment of Catholic social teaching. Specifically, the Pontifical Council for Justice and Peace's “four permanent principles” of human dignity, the common good, subsidiarity, and solidarity highlight the issues involved and help parents navigate this significant medical choice with a more informed conscience and a greater sense of their moral responsibilities. The end result is a fruitful alignment between Catholic social teaching and ethics in ordinary life.