I participated in the STOP POLIO mission in Punjab, Pakistan. The STOP POLIO programme is organised jointly by the Centers for Disease Prevention and Control in Atlanta and the World Health Organization. People recruited to this programme are first trained in Atlanta, and subsequently assigned to various countries. I was assigned to Pakistan, together with a colleague from Ethiopia and from Bangladesh. It was a challenging time, because there were still "wild" polio cases found in the Punjab province. Additionally, Pakistan faced civil unrest. I arrived shortly after the assasination of Osama bin Laden by the US military, who used undercover agents pretending to work for the polio campaign, to confirm the terrorist identity. I was assigned to assist in three mop-up immunization campaigns, organised in various districts. Each campaign took approximately 3-4 weeks from the planning phase until evaluation. In February, I helped with an immunization campaign in Hafizabad, following the detection of a polio case in a neighbouring district. In March, I helped organise a routine immunization campaign in Vehari district, and in April, I moved to Sialkot, where I supervised another campaign in the north-east of Punjab. During my mission, I proposed an improvement of the training of immunization teams and I helped in supervision and monitoring of immunization teams.