Antivaccination activists have existed since variolation was introduced in Europe in the 18th century. Today, they continue to attempt to influence the vaccination decisions of parents. Commentators have expressed concern about the impact of such activists on vaccination rates and disease outbreaks. Some argue that public health advocates should engage in adversarial approaches involving public attempts to discredit or stop an antivaccination group or individual. This article argues that such adversarial advocacy may not be the most effective way to support vaccine programs. It argues this on the basis of what is known to influence vaccination attitudes and uptake, and the unintended negative consequences that can arise from an adversarial approach. These include drawing attention to such activists and their arguments, and potentially alienating the most important audience - hesitant parents - where the primary goal is to establish trust. The exception is when the antivaccination activists' actions may cause direct harm, such as encouraging a 'disease party' or illegal activities. Generally, however, advocacy should focus on areas where real gains can be made - on policies that directly address determinants of low coverage such as lack of opportunity to vaccinate and lack of acceptance of vaccination. This includes advocacy for accessible and affordable vaccines. In addressing the global problem of vaccine hesitancy, public health has a responsibility to better monitor public attitudes, support health professionals in communication, and develop and test strategies that engage vaccine-hesitant parents and communities.