Methods of evaluating a cellular sample for HER-2/neu expression are provided. Aspects of the methods include flow cytometrically obtaining fluorescence emission data from a cellular sample fluorescently labelled HER-2/neu specific binding member and employing the sample fluorescence emission data with standard fluorescence emission data to obtain a value of fluorescently labelled HER-2/neu specific binding members bound per cell. Compositions, devices and kits for performing these methods are also provided
