require would import the symbols and semantics from the package that has the variables at run time, Scoping in Perl is not strictly global, it rather restricts the variables to the package space (which can spread across files), of course it is more robust to control symbols export and import with the Exporter module as ikegami indicated.

The code following is a proof of concept that you may extend upon, I have two files, CheeseSpread.pl which has the variables and CreamIt.pl which uses the variables declared in CheeseSpread.pl. Note, the file boundaries are not synonymous with package boundaries so it is possible to declare the variables in one file and then access them from different files.

#!/usr/local/bin/perl
#title "Wish I could include global constants"
#CheeseSpread.pl
use strict;
use warnings;
package CheeseSpread;

BEGIN{
    our $name = "Mary";
    our $monkish = "MaryFranan";
    }
1;
[download]

#!/usr/local/bin/perl
use strict;
use warnings;
require 'CheeseSpread.pl' #imports the package symbol table;

print name();
print monkish();

sub name{
        return "my name is $CheeseSpread::name\n";
        }
sub monkish {
        return "my avatar is $CheeseSpread::monkish\n";
        }
print "-" x 50, "\n";   # a horizontal rule

my $firstName = $CheeseSpread::name;
my $monasteryName = $CheeseSpread::monkish;
print "my name is $firstName\n";
print "my avatar is $monasteryName\n";
1;
[download]

Another thing, Perl has the h2xs utility that you can use to create Modules template - in the current folder - including test files automatically and as quickly as:

%h2xs -X -A -n Name::Module
[download]

check the Tutorials and the rich documentation on OO Perl..