Some of the seminal steps toward the recognition and definition of brain death were European. There is a general consensus on both the medical concept of brain death in Europe as well as the minimum fundamental clinical standards that are required for its diagnosis—the absence of consciousness, brainstem reflexes, and the ability to breathe in the absence of reversible or confounding conditions. Two aspects of brain death determination are addressed in this article. The authors analyze how brain death is diagnosed across Europe, identifying both the similarities and differences that exist between countries (the latter mainly concerning ancillary tests, timing, and the number of physicians involved in the brain death determination). In addition, they describe the very considerable variations in when brain death determinations are made between and within individual European countries, and propose that they are due to differences in the end-of-life care practices in patients with irreversible brain injuries, medical attitudes, and organ donation practices. Although legislation is available to standardize the brain death diagnosis process in most individual European countries, there are still disparities across Europe as a whole. The current variation in practice makes a continental consensus for the definition of brain death imperative.