La-Di-Day is an event in Animal Crossing: Wild World that occurs every second Saturday of every odd-number month. Villagers participate in a competition for a new Town Tune, except those neighbors who are sick, moving in, or moving out.

Villagers will sing their song to the player and will try to impress the player with their tune, so the player may go to every animal and find the tune that strikes the right note. Tunes that the player would like to be made the new town tune must be responded to with "You're hired!", and the tunes that the player does not want must be responded to with "That won't do". Some villagers may come slightly upset if you don't pick their song (or angry) but it makes them more determined to do better. The last person the player says "You're Hired" to's tune will become the new town tune. The tune will sound different when played as the town tune