The number of people suffering from homelessness is declining across the U.S., even though some cities are seeing increases.

Here are some approaches to the problem that officials say are working:

— HELPING VETERANS — The number of homeless veterans in the U.S. has dropped 47 percent since 2010, according to the U.S. Department of Housing and Urban Development (HUD). That's due in part to HUD's collaboration with the Department of Veterans Affairs on programs that have provided veterans more than 79,000 rental vouchers. The programs emphasize enhanced coordination between veteran service organizations, government agencies, city mayors, faith-based providers, affordable housing operators and nonprofit organizations. About 111,000 formerly homeless veterans have been housed through such programs.

— HOUSING FIRST — The nation saw an overall decline in long term or chronic homelessness "because of our Housing First approach, which provided more permanent supportive housing opportunities for people with disabling health conditions and other needs that require supportive services," said Julián Castro, secretary of the U.S. Department of Housing and Urban Development. The Housing First model offers people housing without requiring checks of their sobriety or mental health stability as a condition to be awarded housing. The program emphasizes that having a home and supportive services first will help stabilize people suffering from problems ranging from alcoholism to mental illness.

— INVESTING IN AFFORDABLE HOUSING — Voters in Los Angeles approved a proposition on Election Day to invest $1.2 billion in safe housing and programs to benefit chronically homeless people. Other cities should adopt similar tax measures to invest in affordable housing and address the shortage, Castro said.

— BRIGHT SPOTS — North Dakota, Vermont and West Virginia had the largest declines in overall homelessness from 2015 to 2016.