Vaccines are a classic collective action problem. Any individual is crazy (or at least technically irrational) to get their kid vaccinated, because, although there is not a consensus of harm in the scientific community, there is at least a medium probability of great harm, making the expected value of a vaccine negative (and certainly much more negative than the cost of filling out a form for exemption). And is your kid going to get measles if they don't get vaccinated? No. That's not how vaccines work. Vaccines work by limiting the population that diseases can prey on, and thus eradicating them in communities. But if NO ONE gets vaccinated, then the disease is likely to resurface in a community, and then your vaccination actually will protect you. What this means is that this problem has no Nash equilibrium--If everyone gets vaccinated, your motivation is to not, and if no one does, you should. So what am I saying? I wouldn't vaccinate my kids either, but if the percentage of vaccination fell below a certain rate, I would reconsider. So LL--stop getting the word out!