New developments in implementation of optical multidimensional spectroscopy are presented. These include broadening the spectral range from terahertz to x-ray wavelengths, expanding the classes of materials that can be studied with the technique. Methods for improving the spatial resolution through, for example, tip-enhanced 2D spectroscopy, are discussed. Other methods for excitation and detection are present, including using non-classical light for excitation and detecting signals through photoemission of electrons.