Saliva for measurement of cortisol is generally sampled by swabbing the mouth with a cotton roll, but this method has drawbacks. In the present study, we evaluated the use of an eye sponge as an oral collection device for saliva cortisol. The eye sponge was compared with commercial cotton rolls, and tested for use in infants as well as adults. Our results show that the eye sponge has adequate cortisol recoveries, even after samples have been kept at 4-8 degrees C for up to a week. In adults, volumes of 200-250 microl are obtained without problem; although smaller volumes are obtained in young infants, they are sufficient for assays requiring only 50-100 microl of saliva. In conclusion, the eye sponge is a valid and adequate collection device for saliva cortisol. Additional advantages as compared to cotton rolls are: more comfortable sampling, tastelessness, no need to manipulate the absorbing material, and the ease with which the untrained eye can determine that enough saliva has been collected.