UNICEF is the world's largest distributor of vaccines to the developing world, supplying vaccines for 36% of the world's children.
In emergencies such as conflict or a natural disaster, we deliver vaccination campaigns to help protect vulnerable children from preventable diseases when health services are down.
There's still a lot of work to be done, but today, 4 out of 5 children are being immunised – that's more than ever before. Find out more in this photo gallery, or visit our page on immunisation and vaccines.
In Syria, a girl receives a dose of oral polio vaccine at a health centre in Damascus, during the UNICEF-supported polio and measles immunisation campaign in 2012. Find out more about our work for Syrian children.
© UNICEF/NYHQ2012-1628/BASSEL HALABI