A passenger compartment with first through fourth placement spaces that include first through fourth accommodation units, where the accommodation units are of a modular design. The first and second accommodation units are a first seat and a second seat which can both be changed between a sitting position and an essentially horizontal resting position. The first and second placement spaces are arranged in one placement plane facing each other. The third placement space is arranged beside the first placement space and the fourth placement space is arranged beside the second placement space. The arrangement includes a delimiting element arranged laterally beside the first and second placement spaces and extending to be perpendicular in relation to the placement plane. First and second couchette elements are affixable to the delimiting element such that passengers can be accommodated who are in positions lying down above the first and second placement spaces.