Diogenes syndrome refers to the combination of extreme self-neglect and excessive collecting with clutter and squalor, which is often present in patients with dementia. Diogenes syndrome may be particularly common in behavioral variant frontotemporal dementia (bvFTD), and the investigation of these patients may help clarify the nature of this syndrome. We describe 5 patients with bvFTD who exhibited a decline in self-care accompanied by hoarding behaviors. These patients, and a review of the literature, suggest a combination of frontal lobe disturbances: loss of insight or self-awareness with a failure to clean up or discard, a general compulsive drive, and an innate impulse to take environmental items. This impulse may be part of the environmental dependency syndrome in frontal disease, with specific involvement of a right frontolimbic–striatal system. Further investigation of the similarities and mechanisms of these symptoms in bvFTD could help in understanding Diogenes syndrome and lead to potential treatment options.