Cardinals are senior ecclesiastical leaders of the Catholic Church, almost always ordained bishops and generally holding important roles within the church, such as governing prominent archdioceses or managing dicasteries within the Roman Curia. They are created in consistories by the pope and one of the foremost duties of the cardinals is the election of a new pope (since 1378 invariably from among themselves, though not a formal requirement) when the Holy See is vacant, following the death or the resignation of the reigning pontiff. The body of all cardinals is collectively known as the College of Cardinals. Under current ecclesiastical law, as defined by the apostolic constitution Universi Dominici gregis, only cardinals who have not passed their 80th birthday on the day that the Holy See falls vacant are eligible to participate in a papal conclave to elect a new pope and are thus known as cardinal electors.
As of 28 June 2018,[update] there are 226 cardinals, 125 of whom are cardinal electors. (Full list...)