Since taking over in March 2013, the 81-year-old Argentinian has championed the cause of the marginalised, saying he wanted a "poor church for the poor" and shunning papal palaces and ostentatious displays of wealth.
His reform agenda has introduced the possibility in certain cases to allow divorced and remarried believers to take communion, although he still agrees with the Church's traditional positions on other issues, such as abortion, artificial contraception and gay marriage.
But the sex abuse scandals have haunted his papacy and last month the Vatican announced it was reviving its anti-paedophile panel. A trip to Chile in January was seen as a resounding failure after he defended a bishop accused of covering up the crimes of a paedophile priest.
Francis, who like his predecessor Benedict XVI, promised a "zero tolerance" approach to sexual abuse, sparked uproar when he said: "The day they bring me proof against Bishop (Juan) Barros, then I will speak." But he later apologised to the victims and sent a Vatican top expert on sex abuse to hear the witnesses in the case.
Marie Collins of Ireland, who was raped as child by a priest, told AFP that while it might be "human nature to want to defend your institution... the Church, instead of learning from the past, is repeating the mistakes of the
"The Church tends to make the same mistake -- in every country where survivors start to come forward, they are treated in the same way," said Collins, who resigned last year from the now revived anti-paedophilia commission.
Francis was similarly lenient towards Don Mauro Inzoli, an Italian priest nicknamed "Don Mercedes" for his expensive tastes. Don Inzoli had been effectively defrocked by Benedict, but Francis overturned that ruling, mitigating his sentence to "a life of prayer."
Nevertheless, after the priest was sentenced to nearly five years in prison in Italy for sex abuse of adolescents last June, the pope dismissed him of clerical duties.
When Francis set up the commission in December 2014 to look into how to protect minors and vulnerable adults in the Church, Collins was one of two abuse survivors to sit on the panel.
Collins walked out in March 2017, denouncing the "shameful" lack of cooperation within the Vatican and complaining that a tribunal announced in 2015 to deal with paedophile priests has never actually been set up. German Cardinal Gerhard Mueller, the Church's top doctrinal watchdog who has since been ousted by Francis, argued that the tribunal would double up with already existing bodies.
Catherine Bonnet, a French child psychiatrist who also sat on the commission, complained that "in three years we only had six plenary meetings in Rome".
"We did have regular e-mail exchanges, but it's hard to debate in that way," she told AFP in an interview. "We have made proposals on important points, but, to my knowledge, Pope Francis has not given answers, which is really worrying.
"The problem is that the pope is extremely busy with many issues. But the issue of protecting today's children is urgent. Children continue to be abused and raped within the Church."
Collins, too, said "the words coming from the pope and the Vatican are very good. The problem is, the actions don't follow through."
For her, the problem was "that those within the Vatican don't see how their actions are viewed from outside." The decision, for example, to hold the funeral of disgraced US Cardinal Bernard Law in the St. Peter's basilica in December may have been within liturgical tradition. But it caused offence to survivors of sexual abuse in the US.
Law, a former Boston archbishop, became one of the main faces of the sex abuse crisis in the Roman Catholic Church after admitting that he failed to protect children from predator priests, despite evidence they had been
Another case casting a shadow over Francis' papacy is the Vatican's finance chief Cardinal George Pell, who is facing committal proceedings in Australia to determine whether he should stand trial on multiple historical sexual
As the Vatican's number three, 76-year-old Pell is the highest ranking Catholic official to face such charges.
The pope did however, oversee a change in Church law in 2016 allowing bishops to be dismissed in cases of "negligence" when reporting incidents of paedophilia. The Vatican also organises awareness classes and the Pope regularly meets with survivors of abuse.
But Church law does not oblige the hierarchy to denounce suspected cases of abuse to the civilian authorities.
"We must be as transparent as possible, it is the duty of the Church to do everything possible to avoid abuses," said German theologian Hans Zollner, regarded as one of the leading experts in the field.