Inhibitory control refers to a person’s ability to control responses and impulses. Deficits in inhibitory control have been found in the neurodevelopmental disorder of Attention deficit hyperactivity disorder (ADHD), though this has mainly been studied in children. This thesis is a systematic review of how inhibition is impacted in adults with ADHD and which neural correlates that are associated with inhibitory control. Only peer-reviewed original articles that used adults above the age of 18 were included. All articles used a between subject design, meaning healthy participants were compared to participants with ADHD. To measure inhibitory control, articles which used either the Stroop Task or Go/No-go task were examined. Nine articles were included in this systematic review. Through functional magnetic resonance imaging (fMRI) altered neural activation was seen in several brain regions, such as the dorsolateral prefrontal cortex, fronto-basal ganglia networks, anterior cingulate cortex, posterior cingulate cortex, parietal lobe and inferior frontal gyrus. Many of these regions have previously been linked to inhibitory control, while others hint at possible compensatory pathways for inhibition in ADHD. In summary, subtle impairments in inhibition networks appear to underlie the disorder all the way into adulthood.