The method involves arranging objects in a group (G), providing the group with a partly covering envelope, inserting at least one group of objects with envelope in a sterilization chamber, sterilising the objects (S), removing them from the chamber and placing the objects and packaging in a packaging arrangement suitable for fully enclosing the group of objects (V). Independent claims are also included for the following: (A) a group of objects in a packaging material to be sterilized (B) and a sterilization system.