A guide rail for guiding a door leaf between open position (III) and a close position (I) 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 (G) for creating a length compensation for the cable when moving the slide element along the guide section , wherein a mounting unit (M) is provided and embodied for disposing the guide rail at the door casing with a DIN left-handed (L) 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 (G) for creating a length compensation for the cable when moving the slide element along the guide section , wherein a mounting unit (M) is provided and embodied for disposing the guide rail at the door casing with a DIN left-handed (L) 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. <EOS>