Backward recognition masking refers to the interference of a second sound on recognition of another sound presented earlier in time. Previous experiments have demonstrated backward recognition masking in an absolute judgment task. In those experiments, all of the experimental conditions were varied randomly within a test session. In the first experiment reported here, backward-masking functions generated between blocks of trials were compared to those determined within an experimental session. The results showed backward masking using both experimental procedures. The next two experiments evaluate backward-masking effects in a two-interval forced-choice task and a successive-comparison task. Backward masking was observed in both experiments. The final experiment showed that selectively attending to the ear of the test tone presentation does not attenuate the backward-masking effects of a second tone presented to the opposite ear. Subject Classification: 65.22, 65.58, 65.75.