Researchers have consistently reported that couples agree about nonviolence but not about violence in their relationship. One theory is that poor memory ability in either the man or the woman in substance-abusing partners may be related to less agreement about the occurrence of IPV. Further, other cognitive deficits also result from polysubstance abuse. The primary hypothesis of the current study was that higher verbal and visual memory scores would be associated with lower levels of disagreement between partners on the subscales of the modified Conflict Tactics Scale-2 (CTS2). Participants were required to be 18 years old or older and either married or cohabiting for at least 1 year. Participants were also required to be sober for a minimum of 14 days prior to testing, and female partners were required to be sober on the day that the interviews were conducted. The men were required to meet DSM-IV criteria for current (past year) dependence or abuse on two or more of nine types of drugs. In addition to the CTS2, participants were administered a battery of neuropsychological tests that measured visual memory, verbal memory, word knowledge, abstract reasoning, inhibition, and attention and visuomotor tracking. Testing results indicated that the men's and women's memory ability, problem solving, disinhibition, and verbal ability were significantly related to disagreement about the most recent IPV episode. This suggests that cognitive ability, particularly memory ability, of the parties should be considered when assessing the accuracy of self-report measures of IPV among individuals diagnosed with polysubstance abuse. 5 tables and 42 references