A constitutional amendment that prohibits people from living in public areas takes effect next week in Hungary.
Campaigners for the homeless say the ban and the threat of prison for violators is unlikely to solve the problem of people sleeping on the streets.
Menhely Alapitvany (Shelter Foundation) director Zoltan Akna said more resources are needed to prevent people from becoming homeless and to house those that do.
Unofficial estimates indicate some 30,000 people are homeless in Budapest, the Hungarian capital.
The Hungarian government says 9,800 places are available in shelters for overnight stays and 19,000 in total.
The government recently allocated 9.1 billion forints (£25 million) to help the needy.