X-Ray Spectra of Early-type Stars Observed with CHANDRA and XMM-Newton}

In this paper I will discuss the temperature, density, and abundance diagnostic tools for X-ray emitting plasmas around early type stars. The methods used are based on individual line fitting, especially applied to the He-like transitions of C, N, O, Ne, Mg, and Si, and on fitting to the total spectrum using SPEX in combination with MEKAL. I will especially focus on biases and possible alternative interpretations for features and observables