Housing mobility, the idea of moving poor families into wealthier neighborhoods where they have access to better schools and services, has been gaining traction in recent weeks. The Supreme Court upheld a decision that forced the state of Texas to shift the construction of affordable housing to areas where little such housing exists. President Obama released a new rule for the way HUD distributes housing money, requiring regions to more carefully integrate their housing stock. But housing integration has downsides. Building new affordable housing in wealthy areas takes investment away from the downtrodden areas that most need it. Moving poor children to better schools can help those individual students, but does nothing to improve the sub-par schools they left behind.