Self-affirmation theory holds that threats to the self can be reduced by focusing on cherished values unrelated to the content of the threat (Steele, 1988). Because threat often leads to defensiveness (Liberman & Chaikin, 1992), self-affirmation can be a useful technique to promote even-handed, non-defensive responding. Indeed, several studies show that people are more accepting of a threatening health message – and more likely to change behavior in accordance with the message – if given the opportunity to focus on personal values prior to reading it (for review, see Harris & Epton, 2009). Self-affirmation can also alleviate the negative effects of threat on task performance and academic achievement, ostensibly because it uncouples performance success from the self-concept (Sherman & Hartson, 2011). Although the body of evidence illustrating beneficial effects of self-affirmation continues to grow, little is known about how self-affirmation opportunities influence affective processes or how the effects of self-affirmation might vary with affective state. Early research found that there was little or no effect of self-affirmation on general mood, reducing the likelihood that self-affirmation effects were a proxy for the effects of positive affect or that positive affect mediated those effects. Instead, we propose that the relationship between self-affirmation and affect is much more nuanced. In particular, we contend that (1) self-affirmation influences more specific affective experiences such as worry and feelings of vulnerability (in contrast to more general affect), (2) rather than being a direct consequence of self-affirmation, general incidental emotions – that is, discrete emotions (e.g., sadness, anger) minimally related to the self-affirmation experience – will moderate effects of self-affirmation, and (3) self-affirmation can alleviate the impairment of performance elicited by negative affective states such as stress.