The Second Lateran Council was an important assembly of the Roman Catholic Church held in 1139 in the Lateran Palace in Rome. Convened by Pope Innocent II, the council aimed to address various issues within the Church, including the reform of clerical conduct and the condemnation of certain heretical movements. One of the key outcomes of the council was the excommunication of those who supported the antipope Anacletus II. The council also reaffirmed the authority of the papacy and established guidelines for the election of future popes, contributing to the ongoing development of Church governance.