The actress has long campaigned for international intervention in the region, where millions have been killed and made homeless by civil war.
During her latest trip, the Rosemary's Baby star dedicated her time to refugee children in a camp in Goz Beida, Chad, five years after her last visit - and she describes her welcome as better than any awards show red carpet.
In a posting on her blog, dated 8 March (10), Farrow writes, "When I arrived at the camp, a chorus of children called out my name; 'Mia, Mia! Honestly, no red carpet accolades could possibly be as rewarding."