American Concrete Institute - www.concrete.org/general/home.asp

American Society of Civil Engineers - www.asce.org/asce.cfm

Asphalt Institute - www.asphaltinstitute.org

ASTM International - www.astm.org

National Asphalt Pavement Association - www.hotmix.org

National Center for Asphalt Technology - www.eng.auburn.edu/center/ncat

National Highway Institute - www.nhi.fhwa.dot.gov/home.aspx

National Precast Concrete Association - www.precast.org

National Ready Mixed Concrete Association - www.nrmca.org

National Stone, Sand & Gravel Association - www.nssga.org

PRI Asphalt Technologies - www.priasphalt.com

The International Accreditation Service - www.iasonline.org

The Portland Cement Association - www.cement.org

Transportation Research Board - www.trb.org

World of Concrete - www.worldofconcrete.com