The following tip is not new; it is based on this post and its comments. However, for the sake of completeness and for future reference I bring here the final version. The question this posts tries to address is: Where to put value converters? Normal Solution Usually, the common place to put value converters is in the resources section. With this in place you can use the value converter with StaticResource syntax: < UserControl.Resources > < local : NotConverter x : Key ="notConverter"...