The simultaneous multi-element analysis of five certified reference material environmental samples (two rocks, two sediments and a sewage sludge) by slurry nebulisation using an inductively coupled plasma atomic emission spectrometer with a segmented-array charge-coupled device detector was carried out. Both single element and multi-element optimisation of plasma conditions are reported including the use of on-board algorithms as well as simplex optimisation. Grinding of the samples was found to be critical. Good agreement between slurry analysis using aqueous calibration standards and an indium internal standard was obtained for sediments and rocks but not for a sewage sludge. The use of a customised, low dead-volume, double-pass spray chamber and carbonisation prior to grinding improved recoveries for the latter sample.