What is the Synod for?

As they gather in Rome for a special synod on the family, Catholic Church leaders insist there'll be no change in Doctrine. So what's the Synod for?

Divorce, cohabiting, abortion, contraception, and same sex relationships are a part of many Catholic families these days so how relevant is Catholic teaching at the heart of the Family. Bishops begin their discussions this weekend but Pope Francis has already spoken publicly about Priests needing to care more and judge less - so will the Synod do more than simply present a church with a kinder face?