The purpose of this study is to investigate in depth the perspectives of sustainability scientists regarding academic air travel, with an emphasis on cognitive dissonance and associated coping and rationalisation strategies. The research design is case study-based, focusing on a sustainability-focused academic unit in Germany. Thematic content analysis was applied to the transcripts of 11 interviews with sustainability scientists. Analytic codes were informed by prior previously identified cognitive dissonance reduction strategies. The research design is interpretative rather than seeking representativeness. Most of the academics questioned experience some degree of cognitive dissonance relating to the disjunction between their sustainability knowledge, attitudes and flight behaviour. While this dissonance relates-as expected-to the inconsistency between pro-environmental attitudes and flying, it also relates to the contradiction of social norms that support academic flying. To resolve feelings of dissonance, the interviewees report behavioural change, suppress inconsistencies and use various justifications that include denial of control, denial of responsibility, comparisons and compensation through benefits.Sustainability 2020, 12, 1837 2 of 14 processes involved in such groups. Moreover, as social role models, their behavior may influence others' intentions to change their own behavior [11,12]. Finally, in terms of the rationale of the study, although there is research concerning the institutional factors that hinder reductions in academic air travel [11,[13][14][15][16][17], research concerning individual-level processes relating to flight reduction is scant [9,18].A variety of individual-level theories are available for helping to explain attitude-behavior gaps. Here we use the theory of cognitive dissonance, as it is arguably the most specifically applicable approach for understanding dissonance per se. It might also be noted that the lesser-known theory of cognitive polyphasia [19,20] proposes that people move between different ways of knowing or rationalities in different social contexts and thus avoid dissonance in this way. This approach arguably also merits further investigation in the context of discretionary flying, but here we focus on the application of cognitive dissonance theory [21].According to the latter, inconsistency between cognitive elements (e.g., between cognitions about attitude and cognitions about behavior) causes aversive feelings in people, characterized by tension and discomfort. In order to reduce these negative feelings, behavior changes are one option, besides attitude changes and further resolution strategies [21][22][23]. Various studies have found that people rather tend to justify their flying behavior or deny its impact, instead of changing their behavior e.g., [2,[5][6][7]9,[24][25][26]. However, few studies of air travel have explicitly based their investigation on the framework of cognitive dissonance [8,10] and none (to our knowledge) have researched sustainability scie...