The aim of this paper is to prove the existence of algebraic models for Nash sets having suitable symmetries. Given a Nash set M ⊂ R n , we say that M is specular if it is symmetric with respect to an affine subspace L of R n and M ∩ L = ∅. If M is symmetric with respect to a point of R n , we call M centrally symmetric. We prove that every specular compact Nash set is Nash isomorphic to a specular real algebraic set and every specular noncompact Nash set is semialgebraically homeomorphic to a specular real algebraic set. The same is true replacing "specular" with "centrally symmetric", provided the Nash set we consider is equal to the union of connected components of a real algebraic set. Less accurate results hold when such a union is symmetric with respect to a plane of positive dimension and it intersects that plane.The algebraic models for symmetric Nash sets M we construct are symmetric. If the local semialgebraic dimension of M is constant and positive, then we are able to prove that the set of birationally nonisomorphic symmetric algebraic models for M has the power of continuum.