Many of the largest cities in the country – such as New York, Chicago and Los Angeles - have forms of such policies.
What about Georgia?
Georgia has outlawed sanctuary cities in the state since 2009.
State lawmakers last year went a step further, in response to the killing of a California woman by a man who was in the country illegally.
The new Georgia law requires local governments to certify they're cooperating with federal immigration officials in order to get state funding.
» Trump's crackdown on immigration focuses new attention on Clayton
Atlanta has said that it remains a welcoming city for immigrants, but stops short of labeling itself a sanctuary city.
College campuses appear to be the next battleground. Nationally, there has been a movement to declare some universities “sanctuary campuses” to shield those students studying in the United States without legal status.
Among Georgia's public universities, the issue appears to be a non-starter. Georgia's Board of Regents said in December that while they respect the rights of students, faculty and staff to express their views, "calls for institutions to implement policies and procedures that may violate state and federal laws are unacceptable."
The incoming president of Emory University – a private school – said it would not be a "sanctuary campus."