The Institute for Sustainable Infrastructure (ISI) has reached its first credentialing milestone since launching the Envision Sustainable Infrastructure Rating System in 2012: More than 500 people and engineering firms have been certified to use the system to plan, construct, operate and rate public works assets to increasing levels of resource efficiency

Public-sector employees account for about one-third of these Envision Sustainability Professionals (ENV SPs). An ENV SP has been trained to address triple-bottom-line sustainability dimensions in project design, construction, and operation.

Infrastructure owners are seeking ways of meeting their sustainability goals and enhance public confidence in the process of civil infrastructure development. Envision meets this need as an in-depth planning guide and rating system used to improve the sustainability aspects of projects. Applicable to all project types, sizes, and complexities, the system has been deployed for stormwater management, roads, watershed projects, water and wastewater, airports, and rail systems.

In 2011, the American Public Works Association, American Council of Engineering Companies, and American Society of Civil Engineers launched the institute to provide a sustainability rating system that would do for public infrastructure what LEED has done for buildings.