The effects of empathy loss in frontotemporal dementia (FTD) and Alzheimer disease (AD) on carer symptomatology were investigated. Carers of patients with 2 clinical subtypes of FTD (behavioral-variant FTD [bvFTD] = 18; semantic dementia [SD] = 14) and AD (n = 18) completed the Interpersonal Reactivity Index (IRI), a standardized questionnaire of empathy as well as a measure of perceived burden (Zarit Burden Interview) and the quality of the marital relationship (Intimate Bond Measure). Patient ratings were also obtained on the IRI. Loss of empathy was most striking in the bvFTD group with a marked discrepancy observed between carer and patient ratings for change in emotional warmth and the ability to take the perspective of others. Empathy loss in bvFTD was associated with a loss of a caring marital relationship. Empathic deficits in SD were milder by comparison to bvFTD and correlated with disease severity and increased perceived carer burden. The behavioral pattern observed in AD differed from the FTD syndromes; deficits were observed only for measures of personal distress with carers reporting that patients were less able to handle emotionally evocative situations. Results highlight that changes in aspects of empathy differ across dementia syndromes and are associated with differing carer and clinical variables. These findings might be explained by the progression of atrophy in regions that are known to be critical for empathy and social behavior and has implications for the delivery and planning of services in dementia.