Given a planar convex
domain Ω, its Cheeger set 𝒞Ω is defined as the unique minimizer of |∂X|∕|X|
among all nonempty open and simply connected subsets X of Ω. We prove an
interesting geometric property of 𝒞Ω, characterize domains Ω which coincide
with 𝒞Ω and provide a constructive algorithm for the determination of
𝒞Ω.