Hi together, I've experienced a problem with \blackboard{} command. Please paste the following code and compile it (I have newest CTX beta version (updating daily)): ------------------------------------------------------------ \starttext Variation 1: $\forall n \in \blackboard{Z} \neq 0$: should be $0$ Variation 2: $\forall n \in \integers \neq 0$: is $0$ \stoptext ------------------------------------------------------------ When the first variation is used, CTX seems to convert every folowing letter into blackboard characters within the rest of the math environment no matter where \blackboard brackets are placed. Only when the second variation with \integers is used, CTX propely converts every following letter. But imagine you need blackboard G for some reason for example. Then the same bug will appear. I hope this can be fixed easily. Greetings, Seba