This thesis investigated the role of secure attachment priming on fear learning. Across a series of five studies, we examined the extent to which attachment primes, as compared to positive-mood matched control primes, could impact fear responses and fear learning. Specifically, we examined the influence of attachment priming on the acquisition, consolidation and extinction of fear memories. Study 1 subliminally presented primes prior to an acoustic startle probe and measured startle reflex and skin conductance as an index of autonomic responding. This study found that the attachment prime inhibited the startle but not skin conductance response after a 4-second delay. Study 2a delivered a visual imagery attachment prime prior to fear acquisition and found that relative to imagery of a positive situation, the attachment prime slowed the capacity for participants to learn to acquire fear, as indexed by fear-potentiated startle. Study 2b examined the role of the above priming methods on the unconditioned response to the aversive shock stimulus and found that the attachment prime did not influence the autonomic fear response to the shock. Study 3 investigated the role of attachment priming on fear consolidation by administering the prime following fear conditioning and examining fear recall the following day. The attachment group demonstrated lower levels of fear-potentiated startle in the fear recall test, indicating reduced fear consolidation. Finally, Study 4 delivered the prime prior to undergoing extinction training. The attachment prime enhanced long-term extinction memory in that it reduced the relapse of fear in a reinstatement test the following day. Taken together, the results presented illustrate novel ways in which fear memories can be modified by attachment priming prior to or following their development, and how safety memories can be strengthened to allow for the long-term resolution of fear memories.