It is easy to find a macro where macro variables were not set explicitely as local leading to potential issues as you already know.   The readonly option of the %global statement could be used in the validation phase as a way to detect each time a global macro variable is updated. This would be especially useful when including macro developed by other persons. It would require a manual review as it is common to update an existing variable e.g %let mymacrovar=%upcase(&mymacrovar.);   But how do we get the list of all the global macro variables defined by the user in a dataset? Dictionary.macros lists all global macro variables included those of the SAS system. There is no user specific attribute in the dictionaries.   *temporary add on when checking for global macro variables; proc sql; create table ref as select name from dictionary.macros where scope='GLOBAL' and name='TEST'; *would need to be able to select all the user defined macro var; quit; data _null_; set ref; call execute ('%' || 'global / readonly ' || name || ';'); run; *Original code to be tested; %let test=A; %macro demo; %let test=B; %mend demo; %demo;   ... View more