This study attempts to give as complete as possible a description of two extinct Saivite sect -- the Kapalikas and the Kalamukhas. In a Christian context the concept of a 'sect' embodies three essential features: a specific doctrine (including a prescribed mode of worship), a priesthood, and a well-defined and exclusive laity. The structure of Hindu 'sects' is in general much more amorphous than that of Christian ones. In most cases more emphasis is placed on doctrine and mode of worship than on organisation. The Sanskrit words most often used for the Kapalika, Kalamukha and Pasupata 'sects' —the groups discussed in this study—are darsana, samaya and mata. The basic meaning of these words is 'doctrine.' Each of the three groups also had its own priesthood. That of the Kalamukhas appears to have been the best organised. Several Kalamukha monasteries (mathas), each under a single head (matha-pati), controlled temples in the regions surrounding them. It is doubtful, however, whether any of the three groups had its own exclusive laity. An ordinary farmer or merchant might have called himself a Buddhist, Jain, Vaisnava, or Saivite, but probably not a Kapalika, Kalamukha or Pasupata. Records indicate that persons supported priesthoods of different and even hostile 'sects' without feeling disloyal. For this reason it might be more appropriate to speak of Kalamukha, Pasupata and Kapalika 'monastic orders' rather than 'sects.' Since, however, the term 'monastic order' does not usually imply a separate doctrinal or philosophical position, we will remain content with the word 'sect.' Unfortunately no religious texts of either the Kapalikas or the Kalamukhas have survived. Their portraits must be drawn from accounts by their opponents and, in the case of the Kalamukhas, from the information contained in epigraphic grants to their temples. The comments on both sects by Yamunacarya and his famous pupil Ramanuja make the best starting point. Many of the remarks by these two Vaisnava sages about the Kapalikas are confirmed and enlarged by the numerous descriptions of Kapalika ascetics in Sanskrit literature.