“I’m Lovin’ It” became McDonald’s global campaign line when the company introduced it in 2003.
The slogan was part of a major worldwide branding effort designed to give McDonald’s markets a more unified voice. Its informal first-person wording was intended to sound conversational and emotional rather than like a description of a particular menu item. The campaign was supported by advertising, packaging, music, and the “i’m lovin’ it” wordmark.
The campaign is especially associated with a short musical hook performed by Justin Timberlake in the launch advertising. Later commercials made the melody and slogan much more prominent than the original celebrity connection.
People sometimes confuse this slogan with “You Deserve a Break Today,” one of McDonald’s most famous earlier campaigns from the 1970s. The two lines belong to different eras: the older slogan emphasized a break, while “I’m Lovin’ It” became the long-running modern global identity.