Warren Spector has revealed to 1UP that close to 275 people are working on his Wii exclusive, Epic Mickey.
"When you have a project this ambitious, you have to go big!" he said.
The figure includes 115 staff at Spector's studio Junction Point, but is boosted by outsourcing. The major production of art assets - such as cut-scenes and level environments - is happening at other firms around the world.
Spector pointed to the huge development teams for Call of Duty: Black Ops and Assassin's Creed II as examples of this trend in game development, although as 1UP points out, it's unusual to see such a large workforce on a Wii-only game.
Epic Mickey is due out in the autumn of this year.