Three analogue experiments examined flooding therapy. Experiment 1 showed that flooding was more effective than standardized desensitization in reducing snake phobia. Experiment 2 examined three different modes of presenting the feared stimuli in flooding: taped auditory presentation, pictorial presentation, and a combination of these two. An additional combination group were given a brief in vivo exposure to the feared object immediately after each of three treatment sessions. Both a behavioral test and subjective estimates of fear showed advantages for the combined group that had the in vivo exposure, although it appeared that auditory instructions to imagine interaction with the snake was the best method for presenting the feared stimuli. Experiment 3 compared the auditory imagined method with and without 'aversive' or 'implosive' scenes, and with either an immediate or a delayed in vivo exposure. The only procedure to produce marked effects was the one that omitted 'aversive' scenes and provided immediate post-treatment in vivo exposure.