How Green Are America's Top Homebuilders?

Calvert to Rank Largest Builders on Environmental and Sustainable Practices

The environmental and sustainable practices of the United States' largest
publicly traded homebuilders will be ranked in a major new report to be
released at 1:30 p.m. EDT on May 6, 2008 by the mutual fund company Calvert,
one of the nation's leaders in the field of sustainable and responsible
investing. Calvert designed the research into homebuilder sustainability with
support from the Boston College Institute for Responsible Investment.

In alphabetical order, the 13 homebuilders covered in the report are: Beazer,
Atlanta, GA; Centex, Dallas, TX; D.R. Horton, Fort Worth, TX; KB Home, Los
Angeles, CA; K. Hovnanian, Red Bank, NJ; Lennar, Miami, FL; M.D.C. Holdings,
Denver, CO; Meritage, Scottsdale, AZ; NVR Inc., Reston, VA; Pulte, Bloomfield
Hills, MI; Ryland, Calabasas, CA; Standard Pacific, Irvine, CA; and Toll
Brothers, Horsham, PA.

News event speakers will be:

* Stu Dalheim, director, Shareholder Advocacy, Calvert; and

* David Wood, director, Boston College Institute for Responsible Investment.

As an investor, Calvert seeks to discern how major U.S. homebuilders compare
on policies, programs, and performance relating to the environment and
resource efficiency. Despite the slump in the overall housing market, the
green building industry is seeing annual growth of as much as 30 percent.
Green building features for new homes present a clear opportunity for the
homebuilding industry -- homeowners are willing to pay a premium for greener
and cleaner homes of $18,500 on average, according to McGraw Hill
Constructions 2006.

TO PARTICIPATE: Join this live, phone-based national news conference (with
full, two-way Q&A) at 1:30 p.m. EDT on May 6, 2008 by dialing 1 (800)
860-2442. Ask for the "Calvert/IRI green building report" news event.

CAN'T PARTICIPATE?: A streaming audio replay of this news event will be
available on the Web at http://www.calvert.com as of 7 p.m. EDT on May 6,
2008.

Calvert is a diversified investment management firm with over $15 billion in
assets under management. Calvert is a leader in sustainable and responsible
investing and manages $6.9 billion in sustainable and responsible asset
management strategies for institutional and individual investors. The firm's
SRI funds have grown to 21, with the most recent additions being the Calvert
Global Alternative Energy Fund (CGAEX) and the Calvert International
Opportunities Fund (CIOAX). Over the years, the firm has built a core line-up
of mutual funds ranging from equity to fixed income, large cap to small cap,
and domestic to international. Calvert also runs the Calvert Social Index(R),
a benchmark for measuring the performance of large, U.S.-based socially
responsible companies. For more information about Calvert or this report
please visit www.calvert.com or call (301) 951-4800.

The Institute for Responsible Investment, a project of The Center for
Corporate Citizenship at Boston College, works with investors, corporations,
public sector organizations, research institutes, and related parties to
coordinate thinking and action around issues of strategic importance to
long-term wealth creation for shareholders and society. In recent years the
IRI has focused on responsible property investing as a key area of concern.

For more information on any Calvert fund, please contact your financial
advisor or call Calvert at 800.368.2748 for a free prospectus. An investor
should consider the investment objectives, risks, charges, and expenses of an
investment carefully before investing. The prospectus contains this and other
information. Read it carefully before you invest or send money.

Calvert mutual funds are underwritten and distributed by Calvert Distributors,
Inc., member FINRA, subsidiary of Calvert Group, Ltd.

May 2008

/PRNewswire-USNewswire -- May 5/
SOURCE Calvert Group, Bethesda, MD; Boston College Institute for Responsible
Investment, Boston, MA

Patrick Mitchell, +1-703-276-3266, pmitchell@hastingsgroup.com, for Calvert
Group