Not compartments, but open overhead racks like the original passenger aircraft. They will easily accommodate airplane carry-on luggage, including wheelies. Although there are no doors, the ride is so smooth that items just stay put. Alternatively, there is often room behind the last row of seats in each compartment that are available on a first-come basis to any passenger. However, if you put baggage there and are not sitting nearby, they now advise you to inform the conductor, as they otherwise may remove unattended bags at intermediate stations.