Two new extemporaneous negative-staining methods are proposed to detect Cryptosporidium oocysts in stools, using light-green and merbromine in 1% and 2% aqueous solution, respectively. A Ziehl-Neelsen stain as modified by Henriksen and Polhenz was used as a reference technique. A comparison between these two new stains and the reference, a modified Ziehl-Neelsen mod. method gave almost identical sensitivity and specificity. We propose their use in routine diagnosis for enteric cryptosporidiosis.