Two-dimensional correlation spectroscopy has recently received keen interest from various fields of spectroscopy because it provides new opportunities for analyzing optical spectra. In the 2D approach, the spectral peaks are spread over the second dimension, thereby simplifying the visualization of complex spectra consisting of many overlapped bands and enhancing spectral resolution. 2D correlation spectroscopy has been applied to a wide range of science and technology such as life science, polymer science, and engineering, food and agricultural technology, as well as material science. This proceedings covers the wide aspects of 2D correlation spectroscopy ranging from theory to applications in these fields. This book offers a good opportunity to learn the state-of-the-art and future trends in 2D correlation spectroscopy.