Window World of Southern Illinois is an affiliate of Window World Inc., America's largest replacement window company and home to the original $189 replacement window. With over 200 nationwide locations and more than 1 million windows installed last year, all Window World stores strive to provide the highest quality window at the lowest possible price. Window World replacement windows not only look great, but they're energy-efficient, easy to clean and affordable. And, because our windows have earned the Good Housekeeping Seal, you can be assured that your project is built and installed to last a lifetime. Window World of Southern Illinois offers double hung windows, bow and bay windows, casement & awning windows, horizontal sliding windows, garden windows, patio doors, french doors, entry doors, garage doors, vinyl siding and professional installation.