Three experiments investigated the mechanisms, correlates, and methods of immunization against interrogative suggestibility (IS). IS involves reliance in memory reports on suggestions contained in misleading questions (Yield) and the tendency to change answers under negative feedback about the quality of previous testimony (Shift). All three studies found that the milder version of the tool used in the studies (GSS) resulted in lower Yield and Shift. In analyses considering the memory states of the participants, IS was found to be highest when participants mistakenly attributed the information contained in the suggestive questions to the original material. However, significant percentages of the participants succumbed to suggestions and changed answers even when they were aware of the discrepancy between the original material and the information contained in the questions. The warning against suggestions was found to lower Yield and Shift, and this was especially true when participants were aware of discrepancies between original material and suggestions. Enhancing self-esteem and inducing mindfulness did not reduce IS. The correlations between IS, including IS in individual mindfulness states, with the Big Five personality traits, anxiety, susceptibility to influence, and self-esteem were inconsistent.