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 different approaches critically with special attention to the position of A. Nünning. In the final section, a four-category taxonomy for the different textual strategies that establishes unreliable narration is suggested. The headlines for the taxonomy are intranarrational unreliability, internarrational unreliability, intertextual unreliability, and extratextual unreliability.