A catwalk is a slightly elevated platform walk designed to demonstrate clothing attires.
The Sims: Superstar[]
Celebrity sims with 3.5 or more stars can do the catwalk in Studio Town. Sims will dress in bizarre clothing and walk down the runway three times. If the catwalk is successful, the sim will gain fame points.
Sims on the catwalk in The Sims: Superstar.
If the catwalk is unsuccessful, the sim will lose fame points and the catwalk director will act dramatically with rage. Celebrity sims with lower than 3.5 stars or who aren't celebrities will be shooed away and are unable to use the catwalk.
The Urbz: Sims in the City[]
Diamond Heights has a functional catwalk where Sims can pose, as well as the Catwalk Club VIP area.
The Sims 2: H&M Fashion Stuff[]
Sims on the catwalk in The Sims 2: H&M Fashion Stuff.
H & M Pleasantville has a de facto catwalk inside the building.
The Sims FreePlay[]
An object called Modelling Catwalk is said to be available, possibly as part of the Catwalk Modelling hobby.
A catwalk is also described as being part of the Cat Show hobby.