In north Dayton — until recently a post-apocalyptic landscape of vacant, gutted houses — 400 Turkish families have moved in, many coming from other American cities. Now white picket fences, new roofs and freshly painted porches are signs of a brisk urban renewal led by the immigrants, one clapboard house at a time. “We want to invest in the places where we are accepted better,” said Islom Shakhbandarov, a Turkish immigrant leader. “And we are accepted better in Dayton.”       
 
Other struggling cities are trying to restart growth by luring enterprising immigrants, both highly skilled workers and low-wage laborers. In the Midwest, similar initiatives have begun in Chicago, Cleveland, Columbus, Indianapolis, St. Louis and Lansing, Mich., as well as Detroit, as it strives to rise out of bankruptcy. In June, officials from those cities and others met in Detroit to start a common network. “We want to get back to the entrepreneurial spirit that immigrants bring,” said Richard Herman, a lawyer in Cleveland who advises cities on ideas for development based on immigration.       
 
... Concerns about uncontrolled illegal immigration, which produced strict curbs in Arizona and other parts of the country, have not been an issue in Dayton. Officials here say their goal is to invite legal immigrants. But they make no effort to pursue residents without legal status, if they are otherwise law-abiding. The momentum for change in Dayton came from the immigrants. In 2010, Mr. Shakhbandarov told the newly elected mayor, Gary Leitzell, that he was thinking of asking Turkish immigrants across the United States to settle here. Most of the Turks in Dayton are refugees who fled persecution in Russia and other former Soviet bloc countries. Mr. Leitzell was intrigued. “I said, the worst thing that could happen is that 4,000 Turkish families could come to Dayton and fix up 4,000 houses,” the mayor recalled. “So how do we facilitate their success?” With 14,000 empty dwellings in the city, officials were open to trying something different.       
 
Officials quickly realized that this city of 141,000 already had a small but fast-growing foreign-born population: more than 10,000 Muslims from different countries; refugees from Burundi and Somalia; college students from China, India and Saudi Arabia; Filipinos in health care jobs; and laborers from Latin America, many here illegally. “The hospitals, the police, the libraries, the service agencies, the landlords, they were all dealing with immigrants, but no one was talking about it,” said Tim Riordan, the city manager. “So we brought it out of the shadows.”       
 
... In October 2011, the City Commission voted unanimously for the Welcome Dayton plan.
Working with local organizations, the city found interpreters for public offices, added foreign-language books in libraries and arranged for English classes. Teachers went back to school to learn other languages. Local groups gave courses for immigrants opening small businesses and helped families of refugees and foreign students. City officials worked with Wright State University, a public institution, to find ways for immigrant doctors and engineers to cut through bureaucracy and gain certifications so they could practice in the United States.
 
The police chief, Richard S. Biehl, ordered officers to no longer check the immigration status of crime witnesses, victims and people stopped for minor traffic violations or other low-level offenses. The police union and sheriffs from nearby counties denounced the policy, saying Dayton had become a “sanctuary city” where immigration law was not enforced.
 
But Chief Biehl defended his approach, saying it allowed the police to focus dwindling resources on serious crimes. Immigrant leaders, especially Hispanics, embraced it, becoming less wary of the police. “If we have any group of citizens who are afraid to talk to us or don’t trust us,” Chief Biehl said, “that’s going to compromise our ability to produce public safety.”
 
...“It’s all about attitude,” Mr. Shakhbandarov said. “Americans maybe have seen better days of Dayton, a better life, better economy. But we never seen that. We have learned to appreciate what we have. And what we have here is much beyond what we ever had before.”
 
..In a national study published last month, Jacob L. Vigdor, an economics professor at Duke University, found that over the last four decades, immigrants helped preserve and in some cases add manufacturing jobs in cities where they settled, sustaining employment for Americans. They also added to local housing values. For every thousand immigrants who moved into a county, 270 Americans moved in after them, Mr. Vigdor found.  Dayton’s immigrant experiment is particularly close to home for one lawmaker who will most likely have a major impact on the debate in Washington: the Republican speaker of the House, John A. Boehner. His district wraps around the city on three sides. But Dayton officials said they were not waiting for Congress. “We’ve found that we can repopulate our city and we can educate the people and inspire them to employ themselves,” Mayor Leitzell said. “In 10 years, when the federal government figures everything out, we’ll be thriving.”