This study investigates the effectiveness of olfactory aversion (OA) and directed masturbation (DM) as forms of conditioning techniques in an adult male convicted of downloading child pornography. The use of OA was employed as an aversive form of conditioning to reduce the occurrence of deviant fantasy. DM techniques were employed as a method of reward to increase the occurrence of appropriate sexual behaviour. The effectiveness of the modifying techniques was measured against a reduction in the frequency and length of time spent masturbating to deviant and non-deviant sexual fantasies, following the olfactory stimuli when paired with DM. After 26-weeks of intervention, results indicate a significant decrease in the frequency of deviant fantasy and time spent masturbating to the deviant fantasy. The reduction in the use of deviant fantasy corresponded to an increase in the frequency and time spent masturbating to a non-deviant fantasy, although the increase was not statistically significant. The use of OA and DM as a method of fantasy control is discussed along with the relative strengths and weaknesses.