Results achieved in different Quaternary sediments by different methods are discussed, especially with regard to the worldwide correlation of Quaternary sediments. The necessity of a mutual checking of isotopic dating results by other geologic, paleontologic, and geophysical methods is stressed. There is danger of overestimating some methods of absolute dating (in Quaternary geology) which has led in many cases to false stratigraphic conclusions. There is danger especially in conditions of continental sedimentation, where the Quaternary is characterized by the alternation of different genetic and lithologic types of deposits. Isotopic methods must be regarded only as one of the existing methods leading to the establishment of a geochronologic scale, considering the many existing breaks of sedimentations.