Errata for the December 28, 2016, version of Gábor Czédli: Cometic functors and representing order-preserving maps by principal lattice congruences Last update: September 6, 2017 The up-to-date version of this file is always available from my website, http://www.math.u-szeged.hu/~czedli/ ( --> publication , find this paper, and click on errata.txt ); the direct link is this: http://www.math.u-szeged.hu/~czedli/publ.pdf/errata-cometic-functors.txt ) An error in the historical overview (Sept 6, 2017): - In the last sentence of the Abstract, change "injective" to "0-separating". Also, do the same in Proposition 4.5 and in the sentence right after this proposition. (I will check if there are other occurrences of the problem ...) A terminological error discovered on August 11, 2017 - The notation and terminology introduced in equation (2.1) seem to be superfluous and they are in conflict with those used in later, see, for example, Definition 3.4 and Theorem 3.6. What we need in Definition 3.4 and Thm. 3.6 should be called the \emph{forgetful functor}, and a different notation should be used. Typos discovered on December 29, 2016 - P9, Definiton 4.4, 1st line: insert "be a functor". - P10, (4.3): insert "in $\cat A$". - P11, Remark 4.8: delete "in" from "see in". - P11 Example 4.10, 1st line: insert "disjoint".