LEED stands for Leadership in Energy and Environmental Design, and is a collaboration between the U.S. Green Building Council, the Congress for the New Urbanism and the Natural Resources Defense Council. The LEED for Neighborhood Development rating system, or LEED ND, integrates the principles of smart growth, urbanism and green building into the first national standard for neighborhood design. LEED certification provides independent, third-party verification that a development’s location and design meet accepted high standards for environmentally responsible, sustainable development.
For the Neighborhood Development certification, at least 50 percent of buildings in the project must meet the LEED criteria. Vail Resorts plans to develop 100 percent of the project’s buildings to meet LEED criteria. Currently, there are no projects registered in the LEED Neighborhood Development program. Ever Vail would be one of the first projects under this newly formed certification.
The LEED-ND rating system, launched in February 2007, was developed to encourage environmentally superior development that brings elements together into a neighborhood, and relates the neighborhood to its larger region and landscape.

According to Wikipedia:  The Leadership in Energy and Environmental Design (LEED) Green Building Rating System, developed by the U.S. Green Building Council (USGBC), provides a suite of standards for environmentally sustainable construction. Since its inception in 1998, LEED has grown to encompass more than 14,000 projects in 50 US States and 30 countries covering 1.062 billion square feet (99 km²) of development area.[citation needed] The hallmark of LEED is that it is an open and transparent process where the technical criteria proposed by the LEED committees are publicly reviewed for approval by the more than 10,000 membership organizations that currently constitute the USGBC.
Individuals recognized for their knowledge of the LEED rating system are permitted to use the LEED Accredited Professional (AP) acronym after their name, indicating they have passed the accreditation exam given by the USGBC.

Benefits and Disadvantages
LEED certified buildings use key resources more efficiently when compared to conventional buildings which are simply built to code. LEED certified buildings are healthier work and living environments, which contributes to higher productivity and improved employee health and comfort. The USGBC has also compiled a long list of benefits of implementing a LEED strategy which ranges from improving air and water quality to reducing solid waste. The fundamental reduction in environmental impacts in addition to all of the economic and occupant benefits goes a long way for making a case for green building. It is also important to note that these benefits are reaped by anyone who comes into contact with the project which includes owners, occupants and society as a whole.
These benefits do not come without a cost however. Green buildings cost more both to design and to construct when compared to conventional buildings. The cost of designing a LEED certified building is higher for several reasons. One reason is that sustainable construction principles may not be well understood by the design professionals undertaking the project. This could require time to be spent on research. Some of the finer points of LEED certification (especially those which demand a higher-than-orthodox standard of service from the construction team) could possibly lead to misunderstandings between the design team, construction team, and client, which could result in delays. Also, there may be a lack of abundant availability of manufactured building components which meet LEED standards. Pursuing LEED certification for a project is an added cost in itself as well. This added cost comes in the form of USGBC correspondence, LEED design-aide consultants, and the hiring of the required Commissioning Authority (CxA) (all of which would not necessarily be included in an environmentally responsible project unless it were also seeking LEED certification).
Often when LEED certification is pursued, the initial construction cost of the project will be higher than the current industry standard. However, these high initial costs can be effectively mitigated by the savings incurred over time due to the lower-than-industry-standard operational costs which are typical of a LEED certified building. Additionally, economic payback may come in the form of employee productivity gains incurred as a result of working in a healthier environment. Studies have suggested that an initial up front investment of 2% extra will yield over ten times the initial investment over the life cycle of the building.[2]
Although the deployment of the LEED Standard has raised awareness of Green Building practices, its scoring system is skewed toward the ongoing use of fossil fuels. More than half of the available points in the Standard support efficient use of fossil fuels, while only a handful are awarded for the use of sustainable energy sources. Further, the USGBC has stated support for the 2030 Challenge, an effort that has set a goal of using no fossil fuel green house gas emitting energy to operate by 2030.[3]
In addition to focusing on efficient use of fossil fuels, LEED focuses on the end product. For example, because leather does not emit VOCs they are deemed healthy for environments, disregarding the use of extremely harmful chemicals in the process of tanning leather. Other products that do not use harmful chemicals and focus on more sustainable production do not earn any additional points for their attention to environmental concerns.