Child immunization is widely acknowledged as one of the most successful and cost-effective investments in public health. Studies estimate that every dollar invested in child immunization yields a return of approximately US $44. Recognizing the significance of early child health in shaping later life outcomes, international organizations such as the WHO and UNICEF continuously collaborate with developing countries to achieve universal immunization. This chapter sheds light on the progress of immunization in Pakistan. It draws on both aggregate data (1980–2021) and household surveys (post-2006) regarding routine immunization and polio vaccination, aiming to analyse immunization coverage not only over time but also across regions, gender, and doses. The findings indicate that immunization coverage for all vaccines was notably higher (around 85%) pre-2008, attributed to better security situations. Contrary to common belief, the gender gap in immunization has narrowed over time. However, compliance with multiple doses shows lower rates in subsequent follow-up doses. Lastly, the province of Baluchistan exhibits the lowest immunization rates for all vaccinations, approximately 25 percentage points lower than Punjab.