BACKGROUND The concept of benign senescent forgetfulness (BSF) was introduced in 1958 by V. A. Kral, consultant neuropsychiatrist to the Montreal Hebrew Old People's and Sheltering Home (hereafter the Home). BSF was criticized and mild cognitive impairment (MCI) was adopted years later. In this paper I argue that a notion of MCI also originated with Kral. METHODS A historical review was undertaken of the Canadian Jewish Congress archives in Montreal, Kral's biography and his publications, as well as relevant literature. A discussion was held with one of Kral's collaborators. RESULTS In the mid-1950s the administration of the Home sought research-derived recommendations to improve residents' conditions. In an initial survey, based on a meticulous neuropsychiatric examination, Kral departed from contemporaneous psychiatric nosology and suggested other criteria in order to classify the home's population. He classified one of the five groups, consisting of subjects with mild memory dysfunction, as having BSF. In his next survey, Kral included psychological tests in addition to clinical assessment and focused on the elderly people who were well preserved (good personal and social functioning). This sample was subdivided into four subgroups, including BSF and incipient amnestic syndrome (IAS). The findings revealed: well-preserved aged people; normal (dull) level of general intelligence; subnormal performance of specific memory and perceptual/organization tests; and no significant signs of malignant amnestic syndrome. This construct is very similar to that of MCI, which is widely used today. CONCLUSIONS The interaction between Kral and a particular home for the elderly at a particular moment in its history gave rise to the concept of BSF, and a notion of what we now call MCI emerged.