A filter-paper method was applied to self- and cross-adaptation in taste. The original method was modified in order to overcome three problems: (i) unreliable replacement of the test stimulus after removal of the adapting stimulus, (ii) incomplete removal of the adapting stimulus liquid, and (iii) migration of stimulus liquid to unadapted surrounding tissue. With NaCl, sucrose and di-quinine sulfate >70% of complete self-adaptation was retained after substituting the adapting stimulus with an identical test paper. Citric acid behaved differently. Only 45% of the complete adaptation survived the change from adapting to test stimulus. It is speculated that this exception of citric acid is due to specific physico-chemical properties of acids combined with the use of the filter-paper method. The experiments show that the filter-paper method provides a useful and reliable procedure for the investigation of cross-adaptation in taste.