Wii Party is a Wii video game by Nintendo. The multiplayer game is a Party type game and a minigame compilation in a similar vein to the best selling Wii Play title.
Executive producer Satoru Iwata has stated that Nintendo decided to move along with Wii Party largely because Mario Party 8, which sold in excess of 7 million copies worldwide, was so popular among gamers. In response to that game, Nintendo hired several employees from Hudson Soft, the developer of the Mario Party games, to develop Wii Party. The team that worked on Wii Party revealed that, when working on Mario Party, they had so many ideas that they would have to shelve them for the next installment in the series. With each new iteration of the series also came new people to work on the game, which in turn brought more and more mini-game ideas. It is possible, though not confirmed, that some of these minigame ideas were brought over to Wii Party.
The developers claim that Wii Party was created due to the team wanting to create a party title with Mii characters instead of characters from the Mario series. They knew that the minigames present would have to be unique, and were afraid that if they didn't accomplish this goal the title wouldn't be able to be a part of the Wii series and instead would have to be called Mii Party.