Transformation of functions refers to a class of stimuli that pertain to a relational frame, and that did not control a particular response, to acquire the function of controlling that particular response under the same context that already controlled another class of stimuli pertaining to the same relational frame to exert that same function. Metaphorically, the function is “transferred” from one class to another in the same relational frame. In tis research, we are interested in the transformation of a particular function: to control fear reflexes and avoidance responses. To find prior literature on this topic, we looked for the concepts of “fear”, “avoidance”, “derived”, and “transfer” (or their synonyms) in PsycINFO, which resulted in 12 papers. Two of-topic papers were removed. We then added 23 papers known to be related to the field. The conditions for the transformation of fear and avoidance functions in a relational frame are discussed.