Every rescue mission is different, and the challenges will depend on a number of factors such as the number of animals, the species involved, the country and borders, the means of transport, any required paperwork, the level of cooperation of the owner and/or of the authorities, the preparation time, etc. One important aspect is the timing of the mission. All stakeholders, which includes the veterinarians, and all the necessary materials and paperwork, such as transport vehicles and permits have to be ready and available simultaneously. The bigger the rescue mission, the more complicated it is to bring these factors together.