Two groups of nonprofit social service providers have been selected by the state to tackle chronic problems with homeless people and juvenile criminals under an innovative new program that will reward the agencies if they can prove their techniques work, or pay them little or even no money if they fail.

The program, called Social Innovation Financing, operates on a simple “pay for success” model, in which nonprofits must demonstrate that by keeping youth from being reincarcerated or the homeless from living in costly shelters, they have saved the state money. Those savings are then shared with the program’s providers and backers.