The U.N. and aid groups generally work with local communities: paying people as contractors, using volunteers, or having leaders appointed by the community as liaisons. The U.N. says it has a zero-tolerance policy for sexual exploitation. Aid groups and experts say exploitation often arises during conflictsReports of abuse and exploitation have emerged during emergencies in South Sudan, Burkina Faso, Congo, Chad and Haiti. Aid groups and experts say exploitation often arises during conflicts and other times of desperation, particularly when people are displaced and reliant on assistance. Despite the stigma, groups say cases are on the riseMany women say they’re afraid to speak up, fearing retaliation and shame if they come forward.