Have you ever heard of cervical cancer? It’s one of the most common forms of cancer among women. Most of the cases occur in countries with lower incomes and fewer resources. The leading cause of cervical cancer is human papillomavirus (HPV). There are several effective vaccines against HPV. But introducing them in the vaccination calendar could cost a lot. Would it be worth it? We used a mathematical model to see if HPV vaccination would be cost effective in Mongolia. It helped us estimate the benefits and costs of introducing an HPV vaccine there. We found out that it would cost between $2.4 and $3.1 million (USD) but could save nearly 4,000 lives! We believe that introducing HPV vaccines in Mongolia would be cost effective.