Quantum-chemical methods of theoretical vibrational spectroscopy allow for the calculation of vibrational energy levels without the need for system-specific parametrizations and can thus close this gap. The calculation of vibrational spectra within the harmonic approximation is well-established and routinely applied for molecules with hundreds of atoms (see, e.g., Refs. 54-57), including molecular systems in aqueous solution. While the calculation of anharmonic vibrational energy levels is less established, most impor-tantly because it is associated with a higher computational effort, tremendous progress has been made in the past decades. Most importantly, efficient approximate schemes for the inclusion of anharmonicities in theoretical vibrational spectroscopy have become available that are applicable to medium-seized molecules, including polypeptides. Here, we extend one such approach, the localized-mode vibrational self-consistent field (L-VSCF) method in combination the with localized-mode vibrational configuration interaction (L-VCI) method, for the calculation of 2D-IR spectra. When applied together with an anharmonic one-mode potential energy surface with harmonic two-mode couplings between localized modes, this approach has been shown to be able to predict anharmonic vibrational spectra accurately and efficiently. Moreover, it allows for a direct connection with vibrational exciton models, without the need for any empirical parametrization.