This paper is organized in three sections. In the first section, we discuss the relevance of comparative psychology to clinical issues by relating resistance to extinction to psychological disorders involving anxiety, addiction, and fetishism. In the second section, we review areas of comparative psychology that deal in one way or another with the general problem of treating an insignificant event as it were significant. We describe research on supernormal stimuli, evaluative conditioning, acquired drives, incentive sensitization, and consummatory response theory. In the third section of the paper, we present new research on second-order sexual conditioning of male Japanese quail related to the consummatory response theory. First-order conditioning was conducted by pairing the presentation of a terrycloth object (CS1 or conditioned stimulus 1) with copulation with a female (the US or unconditioned stimulus). The male quail came to approach the terrycloth object during the first-order conditioning phase. In addition, about half of the quail also showed conditioned consummatory responses directed towards the terrycloth object. During the second-order conditioning phase, the terrycloth object was used to condition responding to a light (CS2) in the absence of further exposures to the unconditioned stimulus. Birds that showed conditioned consummatory behavior towards CS1 persisted in this behavior during the second-order phase and showed successful second-order conditioning of the light. In contrast, birds that failed to develop conditioned consummatory responses to CS1 showed rapid extinction and minimal second-order conditioning. The implications of these finding for learning theory and for psychopathology are discussed.