LIGHTFAIR International (LFI) 2017 is held by Illuminating Engineering Society of North America (IES) and International Association of Lighting Designers (IALD). This year is LFI's 25th anniversary. LFI is currently the largest international lighting expo in the USA and attracts the most amount of visitors among international lighting expos. LFI is held once per year, and it takes turns being held in New York City, Philadelphia, and Las Vegas. LFI is the grand event of luminaire industry in the North America.