We consider the coupled Schrödinger-Korteweg-de Vries system i(u t + c1ux) + δ1uxx = αuv, vt + c2vx + δ 2vxxx + γ(v2)x = β(|u|2)x, which arises in various physical contexts as a model for the interaction of long and short nonlinear waves. Ground states of the system are, by definition, minimizers of the energy functional subject to constraints on conserved functionals associated with symmetries of the system. In particular, ground states have a simple time dependence because they propagate via those symmetries. For a range of values of the parameters α, β, γ, δi, ci, we prove the existence and stability of a two-parameter family of ground states associated with a two-parameter family of symmetries.13359871029Albert, J., Concentration compactness and the stability of solitary-wave solutions to nonlocal equations (1999) Applied Analysis, pp. 1-29. , (ed. J. Goldstein et al.) 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