Ionization affects the energy and shape of the characteristic x-ray lines that may be excited by energetic electrons in a partially ionized plasma. We present the first theoretical predictions for copper K-line spectra in different ionization states, one of a systematic series of computations on how ionization affects inner-shell x-ray lines. Detailed computations such as these may make it possible to use individual hard x-rays lines as diagnostics for warm, dense plasmas when high-resolution x-ray spectra are available.