There are many techniques and materials to fill the root canal system. In this paper a number of the most popular techniques and materials is discussed mainly with the purpose to give an overview, and to understand the advantages and disadvantages of the various types of root fillings. Discussed are sealers based on zinc oxide-eugenol, synthetics and those that adhere to dentine or to which medicaments have been added. Of the various filling techniques the cone cementation techniques like single cone and lateral compaction are discussed, while of the warm techniques the lateral, vertical, and thermomechanical compaction as well as injection and core carrier techniques are described.