For the varies errors and warnings I get from CGI, I like to have a semi-generic module I can call to print to a logfile with the basic information (variable data, short descriptive error message, time/date, line number, some error code/variable to send to HTML::Template (for the user to see), and etc. Note this will not replace Data::Dumper for debugging errors nor die for serious errors, but is very helpful for errors like a param being empty or invalid (esp. if it is in a sub that you can call like this: error() unless defined $someparam;). Just my way of doing things.