My advice is always to avoid global vars whenever possible. They are most always bad (say "I have 30 global variables, is that too many?" in the chatterbox and what happens). Machines are fast. Ram is cheap. I'd rather add a few clock cycles to the execution time than add a few hours to the debugging time.

As for a technique to apply... Instead of having 30 separate variables floating around, stuff similar groups of variables into either a module (as previously described) or use a hash. I describe the technique for using a hash here. Basically this is a best of both worlds scenario...to pass ALL your vars to your module you only have to copy 1 scalar if you us a hash ref (your coworker's big problem), you don't have tons of globals, and you don't have to remember the exact sequence of the 30+ vars you passed in.

HTH

/\/\averick
perl -l -e "eval pack('h*','072796e6470272f2c5f2c5166756279636b672');"