With very few exceptions, all models used in a game of Warhammer: the Old World should be mounted upon a square or rectangular base, the dimensions of which are given here in millimetres (mm). Sometimes, a range of sizes will be given. In such cases, the base the model is provided with is the correct base to use.

Base Sizes (Designer's note)
As stated above, all models used in a game of Warhammer: the Old World should be mounted upon a correctly sized and shaped base. However, many players will have in their collections older models, the base sizes of which can vary. Whilst it is possible to play a game of Warhammer: the Old World without needing to re-base such models, in Matched Play events players are required to use correctly based models to ensure all aspects of the game are as fair as possible. To assist with re-basing an existing collection, separate bases are available as part of the Citadel Miniatures range.