Robert K. Musil

Michael Barrett

self (National Geographic Society)

Lester Brown

self (Earth Policy Institute)

Robert Gard

self (U.S. Army)

David Jensen

self (UN Environment Programme)

Thomas E. Lovejoy

self (biologist, The Heinz Center)

Michael MacCracken

self (atmospheric scientist, Climate Institute)

Alice And Lincoln Day

director

Lincoln Day

director, producer

Alice T. Days

director, writer, producer

Lincoln H. Days

director, writer, producer

Todd Hahn

composer

Wayne Westbrook

cinematographer

Dan Gallagher

editor, writer

Saleem Ali

self

James Janko

self

Martin Luther King

archive footage

John McNeill

self