The mood-dependent retrieval hypothesis states that mood will enhance recall by acting as a recall cue if the stimuli have been learned initially in the same mood. Material learned in a happy mood will be best recalled when the person returns to a happy mood; the same holds for a sad mood. Mood-dependent retrieval effect has been regulary demonstrated but has also regularly failed to replicate in a laboratory setting. Relations between mood states, states in general, and memory are not well understood. A first possible specification of what causes the mood-dependent retrieval effect is experimenter demand. An important precondition for obtaining the mood-dependent retrieval effect is to insure strong mood-inductions. Another moderator of mood-dependent retrieval may be whether or not retrieval cues alternative to mood, such as the room, are available to cue recall. Item-mood associations can be heightened using to-be-remembered stimuli that can be perceived as causing the mood or by having subjects generate their own items for recall while in the particular mood. None of these factors suggested to explain mood-dependent retrieval can do so by itself. If mood dependent retrieval is found in experiments which simultaneously use effective mood inductions, eliminate alternative cues, and enhance mood-stimuli associations, then more reliable demonstrations of mood-dependent retrieval may be possible. (ABL)