Each year in the U.S., ≥20,000 women and 14,000 men are affected by HPV-related cancers, including cervical and oropharyngeal cancer. However, in 2020, only 59% of U.S. adolescents aged 13-17 were up-to-date for HPV vaccination, and rates for 11-12 year olds, the primary target age group for HPV vaccination (when the immune reaction is better and before exposure to HPV infection), are even lower. Standing orders (written protocols that authorize designated members of the healthcare team to vaccinate without first obtaining a patient-specific physician order) have been shown to work in inpatient settings and for adults, but have not been evaluated for HPV vaccine, which some parents consider controversial. Also, the ways in which organizational readiness for change (resources, motivation, staff attributes, leadership support and culture) moderate the effect of standing orders has not been studied. A physician's recommendation is correlated with HPV vaccine acceptance, and the investigators have developed a successful online, interactive, communication education program that will be adapted to train nurses and staff in addition to physicians. The investigators propose testing standing orders for HPV vaccine in an Accountable Care Organization (ACO) in Western New York, and assessing which provider and practice factors moderate the effect of standing orders. Advantages of this setting include a diverse group of rural, urban and suburban practices, and the ACO provides data infrastructure and analytics that allow practices to evaluate vaccination rates in real time. Using a 2-arm cluster randomized trial (n=40 practices), the investigators will assess the effectiveness of standing orders (SO) + HPV communication education (intervention arm) relative to HPV communication education alone (control arm) on HPV vaccination for 9-17 year-olds.