This study examines the relationship between reputational events and business sustainability by assessing the effects of such events on the share prices/market capitalisations of FTSE/JSE Top 40 Index entities. Using event study methodology and Tobin’s Q ratio, the study found that reputational events are associated with significant negative cumulative average abnormal returns on the day of the event announcement and for a period thereafter, highlighting the need for listed firms to include #reputationalrisk within their #riskmanagement management frameworks and for practitioners to implement reputation management strategies.