[talk given at the Amazónicas VI conference, May 24, 2016, Leticia, Colombia] Murui (known to its speakers as búe) is a Witotoan language spoken in southern Colombia and northern Peru. Expression of negation involves affixation of the standard negator -ñe, the negative attributive -ni and the privative -no. Based on the 2009-2016 documentary fieldwork data, this paper provides the in-depth look at forms and functions of basic negation and other associated negative structures and morphemes in Murui.