As an Admin, you can activate the trips module. Users can then create trips, manage trips and link expenses to trips.
How to configure this as an Admin:
1. Go to Admin settings.
2. Go to Advanced settings page.
3. Check or uncheck the right checkbox and don't forget to save.
Activate Trips will activate the trips module. Activate per Diem as a Trip will allow you to link Per Diem Expenses to as part of a created Trip.