Mild cognitive impairment (MCI) is increasingly being conceptualized in the literature as a cognitive disturbance representing a transitional phase between normal aging and dementia. The operational definitions of MCI provide an opportunity for neuropsychologists to detect subtle deficit and monitor cognitive status sequentially in order to determine rate and degree of progression. More importantly, clinical and neuropsychological studies are needed that can better characterize which MCI patients are at greatest risk for conversion to dementia. Preliminary data has also designated MCI as a potential indicator for initiation of pharmacotherapy, with the objective of decelerating rate of progression to dementia. Current criteria and clinical issues related to MCI are discussed, with the objective of better familiarizing clinicians with this syndrome and fostering ongoing investigations.