Abstract: In splicing discrete individual optical fibers to a fiber ribbon cable, a fiber organizer is used for placing the loose fibers in a retainer so that they are located exactly in the same way as in a fiber ribbon cable. The retainer is a separate part which is placed, with its lids in an open position, in a lower, centrally located portion of a main part of the device. The individual fibers are inserted, one by one, in vertical slots which are aligned with each other and are located at each end of the fiber organizer. By a movable, elastic heel they are fed into horizontal, slotshaped spaces having heights or widths adapted to the diameter of the fibers and formed between lower and upper surfaces. When all fibers have been fed into the slot, the retainer lids can be swung down so that the individual fibers are securely retained in the retainer.