The text of Hathatattvakaumudi is a vast compendium on hatha system of yoga practice and philosophy critically edited and published for the first time The text is authored by Sundaradeva. Through this work of the author we come to know that he acquired unstinted mastery over ancient Indian literature on yoga and allied sciences. There are ample number of quotations and citations taken from authoritative scriptures which are presented to substantiate validity and authenticity of every yogic concept and practice. This certainly serves the purpose of propagating the very cause of yoga on the traditional lines.