Hi Hans and all others. Is it possible to add a command to allow users to define their own namespace for commands and modules to avoid problems with macros in the core. I would suggest to use i slightly modified version of the \definesystemvariable command. \def\????prefix {????} \def\@@@@prefix {@@@@} \def\defineuservariable#1{\setevalue{\????prefix#1}{\@@@@prefix#1}} Another question how many letters should we use for our prefixes. Two avoid problems with other users we should use a combination of a user prefix 'xx' (e.g. ws (two letters) or wolf (four letters) for me) and a command prefix 'yy' as already used by ConTeXt (e.g. sf for SpeciFics). --> \defineuservariable{xxyy} or \defineuservariable{xxxxyy} What do you think about my idea. Wolfgang