Pope Benedict XVI will leave behind a Catholic Church grappling with crises from child abuse scandals involving priests to confronting radical Islam as well as struggling to find its place in an increasingly secular Western world.
German cardinal Joseph Ratzinger, who will step down at the end of this month after an eight-year pontificate, was elected pope on April 19, 2005 at a time when anger at clerical abuse was at its height in parts of Europe and North America, shaking the faith of many ordinary Catholics.
In 2008, he became the first pope to express "shame" over the abuse and to meet victims.
But he was criticised for failing to realise the scale of the problem during his previous 24-year career as head of the Congregation for the Doctrine of the Faith, the main doctrinal body of the Church.
Widely seen as an ultra-conservative, the first German pope in history has proved in many ways more flexible and modern than his Polish predecessor.
He was the first pope to speak about the possibility of using a condom, although only in the very specific case of a sex worker with AIDS.
In a book of interviews that came out in 2010 entitled "Light of the World" he said this could be a first step towards a "more humane sexuality".
He has also avoided giving moral lessons and has spoken -- often in a very personal way -- on matters of faith.
Benedict focused his papacy on restoring the Catholic Church's identity, improving the coherence of its message and pushing for a respectful dialogue with other faiths and with atheists.
He has seen himself as a source of stability amid lingering uncertainties following the Second Vatican Council in the 1960s and the pontificate of John Paul II, which was marred by the late pope's long illness and his hugely conservative outlook.
Nicknamed "God's Rottweiler" in Germany for his strictness while at the Congregation for the Doctrine of the Faith, Benedict began stamping his authority on the Church even before becoming pope.
As pope, he preferred to be surrounded by prelates who were loyal to the faith and he was always distant from the intrigues of the Curia, which eventually caught up with him last year.
The "Vatileaks" scandal in which hundreds of confidential papal memos were leaked to the press by his once loyal butler Paolo Gabriele revealed serious tensions in the Vatican, particularly between conservatives and progressives, advocates of transparency and of secrecy.
A reserved man, people who have met him say Benedict is attentive and hospitable in person.
He has been keen to communicate through new media, becoming the first ever pope with a Twitter account.
He has said he believes the Church will be marginalised if it does not keep up with the times.
At the same time, he has also said Christianity will only remain credible in the modern world if it is demanding.
A smaller and more confident Church is preferable to a vague community of faith, he has said.
Concerning internal reforms, he has ruled out any change on the rule of priestly celibacy.
He also opened the door to conservative Anglicans opposed to the ordination of women and gay people.
At the same time, he increased dialogue with Orthodox believers and with Protestants.
Initially shunned by Muslims over some misunderstood and controversial comments linking the religion to violence, he multiplied his appeals in recent years for a peaceful coexistence between the world's two great monotheistic religions.
He has however been less of a diplomat than his predecessor John Paul II, calling for greater openness in China and peace in the Middle East with little tangible effect.