Elisabeth Kübler-Ross significantly advanced psychology's understanding of the process of dying with her influential book, On Death and Dying (1969). She focused on studying terminally ill individuals and outlined five stages commonly experienced when coping with death: denial, anger, bargaining, depression, and acceptance.

In denial, individuals reject the reality of their condition, often thinking, "This isn't true; I feel fine," as a way to protect themselves from emotional distress. Anger emerges when the reality of their situation sets in, leading to feelings of frustration and questioning, such as, "Why me?" The bargaining stage follows, with individuals seeking ways to extend their time, often negotiating with a higher power or internally, thinking, "If I could just have more time, I'd do anything." Depression is characterized by profound sadness and a sense of hopelessness, with individuals withdrawing and questioning, "What's the point of continuing?" Finally, in acceptance, they come to terms with their reality, often finding a sense of peace and thinking, "It will be okay."

Kübler-Ross later expanded her model to include other forms of grief, such as mourning a loved one or coping with life changes like job loss. While her work encouraged psychologists to confront the challenges of death, it has faced criticism. Research has questioned the universality and order of these stages, highlighting that each person's experience is unique and that no single "correct" way to face death or grief exists. Just as people differ in other aspects of life, they also approach the end of life in individual ways.