McDonald's introduced the slogan “I'm lovin' it” in 2003.
The campaign began internationally in Munich, Germany, and became McDonald's first global advertising campaign. Its wording used casual language and a stylized lowercase presentation, helping distinguish it from earlier, more formal slogans.
The campaign also featured a musical identity built around the “ba da ba ba ba” sound. Justin Timberlake appeared in an early promotional video, while Pharrell Williams and Pusha T are associated with the campaign's development and musical history.
The slogan is sometimes confused with “You Deserve a Break Today,” McDonald's best-known earlier slogan from the 1970s. Those are separate campaigns from different eras.