Other groups, including Women in Transition in Louisville, Ky., are looking for properties to occupy, especially as they become frustrated with the lack of affordable housing and the oversupply of empty homes.

Anita Beaty, executive director of the Metro Atlanta Task Force for the Homeless, said her group had been looking into asking banks to give it abandoned buildings to renovate and occupy legally. Ms. Honkala, who was a squatter in the 1980s, said the biggest difference now was that the neighbors were often more supportive. “People who used to say, ‘That’s breaking the law,’ now that they’re living on a block with three or four empty houses, they’re very interested in helping out, bringing over mattresses or food for the families,” she said.

Ben Burton, executive director of the Miami Coalition for the Homeless, said squatting was still relatively rare in the city.

But Take Back the Land has had to compete with less organized squatters, said Max Rameau, the group’s director.

“We had a move-in that we were going to do one day at noon,” he said. “At 10 o’clock in the morning, I went over to the house just to make sure everything was O.K., and squatters took over our squat. Then we went to another place nearby, and squatters were in that place also.”

Mr. Rameau said his group differed from ad hoc squatters by operating openly, screening potential residents for mental illness and drug addiction, and requiring that they earn “sweat equity” by cleaning or doing repairs around the house and that they keep up with the utility bills.

“We change the locks,” he said. “We pull up with a truck and move in through the front door. The families get a key to the front door.” Most of the houses are in poor neighborhoods, where the neighbors are less likely to object.