The current methods for the control of the illegal use of anabolics in cattle breeding are far from satisfactory in terms of specificity and sensitivity. Here we describe a method for the simultaneous detection of diethylstilbestrol, zeranol and trenbolone in plasma and edible cattle tissues. The method is rapid (total analysis time 30 min), specific and sensitive (ppt level). The technique employed is a tandem mass spectrometric method: collisionally activated decomposition mass-analysed ion kinetic energy (CAD MIKE) spectrometry. Detection involves the injection of the crude ethanol extracts of plasma and tissues and selection/collision of molecular ions of each targeted compound. Confirmation of the presence of particular compounds is made by matching the complete CAD spectra so obtained with those of the pure compounds.