Abstract: In a series of directed-forgetting (DF) experiments it was found that inhibition of a to-be-forgotten (TBF) list could be disrupted by a secondary task and completely abolished by a concurrent memory load during second to-be-remembered (TBR) list learning . Similarly, inhibition was found to be wholly abolished when the TBF and TBR list were strongly associated but not when weakly associated. These findings suggest that inhibition in the DF procedure depends on how powerfully the second TBR list competes in memory with the representation of the TBF list. When the representation of the TBR list is impoverished or when it is too similar to the TBF list then competition is weak and inhibition is as a consequence weak or does not occur at all.