We study a derivative nonlinear Schrödinger equation, allowing noninteger powers in the nonlinearity, |u| 2σ ux. Our main theorem is short-time existence of solutions with initial data in the energy space, H 1 ; this is achieved by a careful use of the energy method. For more regular initial data, we establish not just the existence of solutions but also the well-posedness of the initial value problem. These results hold for real-valued σ ≥ 1, while prior existence results in the literature require integer-valued σ or σ sufficiently large (σ ≥ 5/2), use higher-regularity function spaces, or impose a smallness condition on the initial data.