This article examines the effects of negative and positive framing of ad claims on consume~s choices and attitudes. Propositions about how the extent of processing before choice affects the relative impact of claims-related versus advertising tactics-related cognitions are tested in three experiments. Findings suggest that when processing is limited, claims-related cognitions have a greater impact on choice, which results in the sponsoring brand being chosen more often when the ad claims are negatively framed than when they are positively framed. When respondents engage in more extensive processing before choice, tactics-related cognitions become more accessible and, if perceived to be unfair, result in an attenuation of the advantage of negative framing over positive framing. A different pattern of results is obtained when one examines brand attitudes rather than brand choice. Copyright 1997 by the University of Chicago.