This paper explores the structure groups G (X,r) of finite nondegenerate set-theoretic solutions (X, r) to the Yang-Baxter equation. Namely, we construct a finite quotient G (X,r) of G (X,r) , generalizing the Coxeter-like groups introduced by Dehornoy for involutive solutions. This yields a finitary setting for testing injectivity: if X injects into G (X,r) , then it also injects into G (X,r) . We shrink every solution to an injective one with the same structure group, and compute the rank of the abelianization of G (X,r) . We show that multipermutation solutions are the only involutive solutions with diffuse structure group; that only free abelian structure groups are biorderable; and that for the structure group of a self-distributive solution, the following conditions are equivalent: biorderable, left-orderable, abelian, free abelian, torsion free.G (X,r) = X | xy = σ x (y)τ y (x) for all x, y ∈ X 2010 Mathematics Subject Classification. 16T25, 20N02, 06F15.