A-PLUS 

A Public-Private Partnership (P3) is defined as a relationship, typically contractual or agreement, established between public and private sector organizations where some services under the responsibility of the public sector are provided by the private sector.  The duration of a P3 is typically medium (10 years) to long (25 years) where there is a clear agreement on shared objectives for delivery, maintenance, or construction of public infrastructure and/or public services. The A-PLUS's primary focus is on the horizontal infrastructures in the roadway, water, electric, and telecommunication sectors. As shown in our "continuum" matrix below, an effective P3 is designed to satisfy the risk, benefit, and control objectives of all P3 members. Also shown below are four typical engagement models1. After a review of these models, A-PLUS works with its partner communities to select the appropriate model and clearly defined the P3 details while adhering to all existing and anticipated future federal, state, and local regulations and policies.

http://ppp.worldbank.org/public-private-partnership/overview/what-are-public-private-partnerships