Brain fog is a cognitive symptom experienced by people with chronic conditions, such as systemic lupus erythematosus and fibromyalgia, and is poorly defined. Research investigating brain fog has produced varying results that do not create a cohesive definition for brain fog. We designed a qualitative study to investigate how brain fog is individually experienced by members of different chronic condition populations to understand the underlying features of this symptom, including impacted cognitive symptoms, impacts to social relationships, and how healthcare professionals view this symptom and approach treatment. Participants were interviewed and asked questions that address the individual experience of brain fog. To date, we have interviewed 87 participants with varying conditions. We use grounded theory to explore the cognitive systems impacted by brain fog.