To be able to arrange travel for other staff, you must be set as an authorized arranger for those staff.
This may have already been organized for you, in which case you won't need to do anything. There are two ways arrangers can be attached to staff - either an individual arranger can be attached or a group of arrangers can be. A group of arrangers is known as an Arranger group.
To check whether you are authorized to arrange travel for someone:
Tip: If you are searching for arranger groups, once the list of results shows, you can see who is contained in each arranger group by clicking on its name.
Tip: Another way to add yourself, or an arranger group, as an authorized arranger, is to ask the traveller to do it themselves. They can do this by going into their profile, clicking Authorized arrangers under the my Details menu, and then following the same process to search for and add yourself as the authorized arranger.