<p> Despite past discussion of uncertainty as a part of therapeutic theory and practice, few researchers have studied how uncertainty is understood by currently practicing clinical psychologists. Through semistructured interviews, 4 clinical psychologists provided their lived experiences of how they define, become aware of, experience, and make sense of uncertainty in their work. Their accounts were analyzed using interpretative phenomenological analysis, resulting in 16 superordinate themes. These included: (a) defining uncertainty as beyond knowledge, inevitable, future-bound, and from complex sources; (b) becoming aware of uncertainty in interrelating with others and in fulfilling professional roles; (c) experiencing uncertainty as distressing and/or threatening; and (d) reacting through reducing/controlling/rejecting, distancing, questioning themselves, seeking out other perspectives, embracing uncertainty, applying uncertainty, using hope and faith, and experiencing uncertainty as professionally taboo. Findings are discussed individually and integrated according to several dissonances/paradoxes emerging from the analysis. Recommendations are provided for clinicians, researchers, training programs, and students regarding experiencing uncertainty and new opportunities for incorporating the impact of uncertainty into clinical research, practice, and education.</p>