Andersen Windows Fiberglass + recycled wood ("Fibrex"), wood, clad wood windows and doors.  Replacement windows and doors.  Headquarters in Bayport, MN., distributed throughout United States

Atrium Windows & Doors Aluminum and vinyl windows and doors,replacement windows and doors.  Headquarters in Dallas, TX., products distributed throughout United States.

Gorell Windows & Doors Replacement vinyl windows and doors.  Headqurters in Indiana, PA, products distributed east of the Mississippi (check their website for dealers in your area).

Hurd Windows & Doors Wood, aluminum-clad wood, vinyl, and combination windows and doors (i.e., all wood interior, nine species, vinyl frame, aluminum cladding).  Headquarters in Medford, WI, products distributed throughout United States.

Jeld-Wen Wood, aluminum-clad wood, vinyl, and aluminum windows and doors.  Exterior doors manufactured from wood (species include mahogany, walnut, oak, hemlock, pine, alder cherry and juniper), fiberglass, and steel.  Interior doors and garage doors.  Replacement windows.  Headquarters in Klamath Falls, OR, products distributed worldwide.

Kolbe & Kolbe Millwork All-wood,  alulminum-clad wood, and vinyl windows.  Exterior doors made of wood or vinyl.  Interior doors.  Replacement windows.  FSC plantation-grown woods available.  Headquarters in Wausau, WI, distributed throughout United States.

Marvin Windows & Doors Windows and doors manufactured of all-wood, aluminum-clad wood. Forest Service Certified plantation-grown woods available.  Fiberglass windows and doors ("Integrity"),  replacement windows and doors ("Infinity"). Headquarters in Warroad, MN, distributed throughout United States.

Milgard Doors and windows with wood interior with fiberglass-clad exterior ("Essence"), vinyl windows and doors, fiberglass windows and doors ("Ultra"), and aluminum windows, doors, and skylights.    Headquarters in Tacoma, WA, distributed throughout United States.

Pella Corportion All-wood windows and doors (with "Endura-Guard"), fiberglass ("Impervia"), and vinyl available.  Selection of glass thicknesses, plus between-glass blinds and shades. Replacement doors and windows.  Headquarters in Pella, IA, distributed throughout United States. 

PGT Industries Impact-resistant doors, windows, and outdoor room enclosures, available in vinyl and aluminum.  Headquarters in Venice, FL.  1,300 independent distributors; get information about local availability on their website.

Ply Gem Windows Vinyl and aluminum windows and doors. Replcement windows and doors. Headquarters in Cary, NC, distributed throughout United States.

Silver Line Windows Vinyl windows and doors manufactured specifically for East Coast and West Coast.  Replacement windows. Headquarters in North Brunswick, NJ, a subsidiary of Andersen Windows and Doors, distributed throughout United States.

Simonton Windows Vinyl windows and doors.  Replacement vinyl windows and doors.  Headquarters in Pennsboro, WV, distributed throughout United States.

Thermal Industries Vinyl windows and doors, and sunroom enclosures.  Replacement vinyl windows and doors.  A subsidiary of Atrium Doors, with headquarters in Pittsburgh, PA.  Distributed throughout United States.

Weathershield Windows and Doors All-wood, aluminum-clad wood, vinyl-clad wood, vinyl, fiberglass-clad wood windows and doors.  Headquarters in Medford, WI, distributed throughout United States.

Leakproof skylight:  http://www.veluxusa.com

Triple-glazed "Energy Core" windows: http://www.mikronvinyl.com

Fiberglass exterior doors in multiple sizes and styles, "FiberLast": http://www.jeld-wen.com