The Nanny McPhee and Love Actually star has just come back from a visit to the west African country.
Liberia has Africa's first female president. But it also has one of the highest rates of violence against women in the world.
The British star was filmed as she travelled round the country with her adopted son, Tindy Agaba, a former child soldier, as they met president Ellen Johnson Sirleaf and visited a cassava farm and a radio station run by women.
“Neglect of girls is widespread in Africa because many families place a lower value on their daughters compared to their sons,” she said speaking after the trip.
“Girl’s bodies are seen as a commodity and one of little economic value. This has to stop," she said.
“I met girls on my trip who told me that they are even expected to trade their bodies for good grades at school.
“Girls bodies are for them to use as and when they please. Not for anyone else. Women should have complete jurisdiction over their own bodies no matter where they live in the world.”
“I have been inspired by the strength, tenacity and work ethic of the women I have met in Liberia - from the nation’s first female radio journalists to the women farmers I carried potatoes to market with.
“Liberia must urgently invest in its most critical resource – its women.”
Emma and Tindy visited Liberia with ActionAid , an international anti-poverty organisation which she is an ambassador for.
“Liberia unfortunately has one of the highest epidemics of violence against girls and women in the world,” said ActionAid’s Joanna Kerr.
Liberia became well known in the 1990s for its long-running civil war in which at least 250,000 people were killed and many thousands more fled the fighting. The conflict left the country in economic ruin and overrun with weapons. Corruption is rife and joblessness and illiteracy are widespread.
The country launched a national education policy for girls in 2006 aimed at ending illiteracy and boosting development. President Sirleaf called it a ‘commitment to our children and a unique opportunity to chart a new course of education for the girl child and for women.’