Khadira Grihya Sutra is a text in aphoristic style of the later Vedic period. This text lays down the religious rites to be performed by a follower of Sama Veda. It is divided into four major patalas (sections) and the first three sections divided into five khandas (sub-sections) each, and the last four.
There are two texts for the Samavedins laying down the rules for domestic rituals. They are Khadira Grihya Sutra and Gobhila Grihya Sutra. The latter is very elaborative while Khadira Grihya Sutra is concise. This text agrees with Gobhila both in the words of the text and in the practice of the rituals. Hence there are two opinions as to the relationship between Khadira and Gobhila – the latter is the elaboration of the former; and the former is an attempt at an abbreviation of the latter.
Khadira Grihya Sutra starts with descriptions of the time for performing domestic rites, the method of wearing the sacred thread during different rites, the definition of religious bathing and connected matters like seating, priests and the way the hands are to be held while performing rites. It then proceeds with marriage, maintenance of nuptial fire, and the daily offering known as vaisvadeva.
The nuptial fire is specifically defined as domestic fire and rites performed with it are known as domestic rites. An option is given to treat the fire in which the final offering is made as reusable, as domestic fire and marriage rites can be performed in it too (1.5.2). The second section deals with prenatal and postnatal ceremonies, fortnightly offerings and initiation and completion of studentship (upanayana and samavartana). Annual commencement of upakarma (Vedic studies), study holidays, agrayana (harvest rituals), and ashtaka (a ceremony to please ancestors) are treated next. Prayers and rites to fulfill different wishes, the conduct of a person like the need for fasting, etc. at such ceremonies, and prayers for success at the Royal court are dealt with in the last book. It ends with madhuparka (ceremony for receiving the guests). This book has been commented upon by Rudraskanda.
Source - Encyclopedia of Hinduism Volume VI page 55 IHRF - Rupa 2011