In many situations, substance abuse can begin as a result of homelessness or can also be a cause of homelessness.  Sometimes, addictive disorders can cause people to lose their jobs or send their relationships with family and friends into a downward spiral. Housing can also be lost if people begin abusing substances or if their current usage gets worse while they’re already struggling to pay bills. In 2008, a survey conducted by the US Conference of Mayors asked 25 cities to cite their top three causes of homelessness. In conclusion, 68% of the cities reported that substance abuse was the single largest cause of homelessness for single adults. In addition, according to Didenko and Pankratz (2007), two-thirds of homeless people report that drugs and/or alcohol were a major reason for their becoming homeless.