A guide rail for guiding a door leaf between open position and a close position with regard to a door opening in a wall extending in an extension plane, which a door casing delimits, including: at least one guide section with a guide space, in which a slide element is movably accommodated, wherein the guide section includes a guide opening, through which a support axis of the slide element exits at least partially from the guide space, at which a lever element is rotationally mobile supportable for establishing an operative connection between the slide element and the door leaf, at least one functional section, with a functional space, in which is accommodated a transfer means in the shape of a cable, which serves for transferring electric energy and/or data between at least one casing-sided energy source and a door leaf-sided energy recipient, and with a transmission for creating a length compensation for the cable when moving the slide element along the guide section, wherein a mounting unit is provided and embodied for disposing the guide rail at the door casing with a DIN left-handed or a DIN right-handed R) door leaf on a pull side (In) or a push side (Out) of the door casing, characterized in that, in the mounted condition of the guide rail, seen in a transverse direction (y) to the extension plane (x, z) of the wall, the functional section is spaced apart and a second functional section with a functional space is disposed neighbouring the extension plane (x, y) of the wall, so that the guide section is disposed between the functional section and the second functional section, wherein, seen in cross-section of the guide rail, a respective one of the functional sections is formed on the left and right next to the functional section, wherein a transfer means occupies respectively only one of the two functional sections and the second functional section, which remains free, can be occupied with another function, for example for accommodating a smoke detector, a hold-open device or the like. at least one guide section with a guide space, in which a slide element is movably accommodated, wherein the guide section includes a guide opening, through which a support axis of the slide element exits at least partially from the guide space, at which a lever element is rotationally mobile supportable for establishing an operative connection between the slide element and the door leaf, at least one functional section, with a functional space, in which is accommodated a transfer means in the shape of a cable, which serves for transferring electric energy and/or data between at least one casing-sided energy source and a door leaf-sided energy recipient, and with a transmission for creating a length compensation for the cable when moving the slide element along the guide section, wherein a mounting unit is provided and embodied for disposing the guide rail at the door casing with a DIN left-handed or a DIN right-handed R) door leaf on a pull side (In) or a push side (Out) of the door casing, characterized in that, in the mounted condition of the guide rail, seen in a transverse direction (y) to the extension plane (x, z) of the wall, the functional section is spaced apart and a second functional section with a functional space is disposed neighbouring the extension plane (x, y) of the wall, so that the guide section is disposed between the functional section and the second functional section, wherein, seen in cross-section of the guide rail, a respective one of the functional sections is formed on the left and right next to the functional section, wherein a transfer means occupies respectively only one of the two functional sections and the second functional section, which remains free, can be occupied with another function, for example for accommodating a smoke detector, a hold-open device or the like.