The Chaturdandiprakashika (IAST: Caturdaṇḍīprakāśikā; "The Illuminator of the Four Pillars of Music") is a Sanskrit treatise written by the musicologist Venkatamakhin in the mid-17th century. It introduced a theoretical melakarta system to classify and organise ragas in the Carnatic music tradition of India. In the 20th-century, this system would form the basis of the thaat system that is used in Hindustani classical music today. Some portions of the Chaturdandiprakashika are now lost.