The concept of the unreliable narrator is among the most discussed in current narratology. From being considered a text-internal matter between the personified narrator and the implied author by Booth, or the implied reader by Chatman, cognitive and constructivist narrative theorists like A. Nünning have described it as a reader-dependent issue. The detection of a narrator's unreliability is an act of 'naturalization,' he claims, with reference to Culler.This article concentrates on this long and ongoing debate and considers the di¤erent approaches critically with special attention to the position of A. Nünning. In the final section, a four-category taxonomy for the di¤erent textual strategies that establishes unreliable narration is suggested. The headlines for the taxonomy are intranarrational unreliability, internarrational unreliability, intertextual unreliability, and extratextual unreliability.