Dharma Sutra is the temporal duty and this form the fourth part of Kalpasutra. Dharma Sutras are closely connected with the Grhya Sutras and they were perhaps written in continuation with them. By Dharma the Hindus mean right, duty law and also religious custom and usage. So at many places the contents of Dharma Sutras and Grhya Sutra overlap each other. The later describe the domestic rites the householder was required to perform in his individual capacity, where as the former were concerned with rules and regulations about the conduct of man as the members of Hindu community and do not involve rituals of any kind.

The Dharmasastras deal with Varnas (casts) and the Ashramas (stages of life). It is under the Ashrama Dharma that the rules of Upanayana and Vivaha are given exhaustively. They also contain rules about Samavartana, Upakarma, the Anadhyayas, Asaucha, the Sraddhas and the Madhuparkas. Dharma Sutra takes up the social aspect of the Samskaras that were simply suggested in the Grhya Sutras. The division of property and such were also discussed in Dharma sutras. There are also lots of Smriti literatures which also discuss Dharmic rules. So, they are also some times called as texts on Dharma. The Smriti texts like Manusmriti have legal and administrative content in it. They are rules of the land and thus contain punishment for the wrong. But the Dharmic treatises said in Kalpasutra focus on moral progress of individual and society and they do not contain punishment for lapse.