As per Vedic or Hindu astrology horoscopes of the boy and girl before marriage are matched for knowing the compatibility between them. There are certain conditions for cancelation of various dosha

The match making system as per Vedic astrology is also called Guna Milaan which means Comparison of Qualities. In this system there are eight factors each carrying different points. Total points are 36, a score of 20 or more gives a green signal for marriage alliance.

Under certain conditions each of these dosha stands cancelled as described here: