A tone (S) was established as a secondary reinforcer for rats by making it the discriminative stimulus for a response (R-sub(1)) which was reinforced with water. When S was used as a secondary reinforcer for a new response (R-sub(2)), its effectiveness was greater when R-sub(1) followed S (R-sub(2)-S-R-sub(1)) than when a new response was required after S (R-sub(2)-S-R-sub(x)). It was suggested that "secondary reinforcers facilitate performance rather than strengthen associations." (PsycINFO Database Record (c) 2006 APA, all rights reserved)