Objective: Cognitive functioning and bilingualism have been important areas of study over the past decade. The aim of this study was to systematically review the literature addressing the association between cognitive deficits in Mild Cognitive Impairment (MCI) and Alzheimer's disease (AD) and bilingualism. Data Collection: A thorough search of databases was conducted using ProQuest, PsycINFO, and PubMed. Inclusion criteria included peer-reviewed articles only, published 2006 – 2016. A total of ten articles were included in this review. Keywords searched included: cognitive impairment and bilingualism, cognitive functioning and bilingualism. Data Synthesis: Seven out of the ten studies suggested that the active usage of two languages contributes to the delay of cognitive impairment. One study compared bilingual and monolingual individuals and demonstrated that bilingual individuals have a significant difference in the age of onset and progression of symptoms associated to MCI and AD. While monolingual individuals were on average 72 years old, bilingual individuals were 77 years when they start noticing cognitive problems showing an approximate age difference of 5 years. Conclusion: Although the results of these studies suggest that a protective effect of bilingualism in delaying the onset of cognitive impairment exits, it was also noted that bilingualism by itself is not enough to completely halt MCI and AD symptoms. The implications of these results may contribute for the development of preventive practices to treat individuals with MCI and AD symptoms. Further studies are needed to confirm these findings and determine the extent in which bilingualism is related to language and other areas of cognition.