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diplomatic, official and no-fee passports
When someone is requested to travel for the government, the Special Issuance Agency will issue him a no-fee passport and to every authorized relatives. However the authorized relatives must obtain their own no-fee passport. This no-fee passport (either diplomatic, official, or regular no-fee US passport) depends on the kind of travel, so the Special Issuance Agency will decide which kind of passport is more appropriate for each case.
It is important to point out that individuals with a no-fee passport can only make use of them while they are carrying out the activities that motivated their issuance. For other activities, they must use their normal US passport.
Given their nature, no-fee US passports are not delivered. You need to contact the travel office of your agency or service for instructions on how to process your passport application and you will have to pick it up there, once approved. Despite these provisions, you may be charged a $30 execution fee for the issuance.