Beginning over the weekend, the two-year process will see every Catholic priest consulted, in a bid to determine the future path of the Church.
Some Catholics believe it could be a major step forward for the organisation, and hope it will lead to change on issues such as women’s ordination, married priests and same-sex relationships.
Meanwhile, more conservative Catholics fear it will undermine the principles of the Church.
It comes as concerns grow about corruption and Church attendance levels… with some saying the reform will distract from these issues.
Pope Francis is urging followers to not “remain barricaded in certainties” but to “listen to one another” following a mass in St Peters Square to signify the beginning of the reform process.
Over the course of two years, the process will have three phases including a “listening phase”.. a “continental phase” and a “universal phase” which will see a month-long gathering of the bishops a the Vatican in October 2023.