Theoretical methods currently used for calculations and modeling of line position and intensities for rovibrational transitions in high-resolution molecular spectra are briefly reviewed. Problems related to an accurate description of bands corresponding to large DV, to high rovibrational states and intensity anomalies are illustrated with examples for isotopic species of О3, H2S, and Н2О molecules. Some features of a new generation of spectroscopic databanks, which contain information on potential/dipole moment functions and global predictions are discussed.