An exchange programme between Threshold and the New York Department of Homeless Services (DHS) has been established to share best-practice solutions to ending homelessness.
The agencies will conduct joint research and share different approaches to dealing with homelessness.
Staff from both agencies will be able to go on exchange internships for learning purposes.
The New York agency has experience in providing housing for homeless people who are mentally ill or disabled.
Threshold director Patrick Burke said he is very impressed with the New York agency's ability to provide a detailed daily count of the homeless on the streets.
Threshold was impressed with New York mayor Michael Bloomberg's Uniting for Solutions Beyond Shelter programme.
"This new partnership offers both Ireland and the US the benefit of accumulated wisdom and experience on how to effectively address the needs of people experiencing homelessness and poverty," said Mr Burke.
He said that Ireland faced a challenge in providing accommodation for single people who are homeless and that capital investment was needed in this area. He added that the availability of traditional bedsits are in decline and that new apartments being built do not cater for single occupants.
Threshold is keen to learn about long-term public housing that is provided for the homeless in New York. In return, the New York agency is interested in Threshold's Access Housing Unit which helps the homeless to obtain private rented accommodation. It is also interested in the Government's rent supplement scheme.