The utility of cognitive therapy (CT) for ambulatory cancer patients is clear but the acute cancer setting significantly shapes the therapeutic interaction, parameters, and delivery of CT. In this article, we describe how to apply CT to acute cancer settings, focusing on how this approach differs from traditionally taught, ambulatory CT. We highlight the importance of a tailored history and formulation, how the cognitive model is applied within an acute cancer context to promote coping and adaptation. Reframing must consider the "grain of truth" to many so-called distorted cognitions, such as "cancer means death." Fear of recurrence is an example of a common reframing challenge. Another is the "tyranny of positive thinking." Here there is avoidance of considering negative outcomes such as death; patients are told to "think positive," leaving them alone at a time of life-threatening crisis. Instead, acute cancer CT utilizes a stance of realistic optimism. Empathy plays a vital role in turning off the bracing reaction to threat and facilitating problem-solving. Successfully combining CT with medications is integral to this model. We also discuss how CT can be applied to discussing prognosis, the desire for hastened death and suicidality, as well as death and dying in general. Because of the ubiquitous nature of cancer, most cognitive therapists will encounter patients with cancer in their practices. Acute cancer CT is a skill set that should be widely taught to cognitive therapists and flagged as a priority for academic programs and professional organizations.