use MP3::ID3v1Tag; # Adds the library $mp3_file = new MP3::ID3v1Tag("filename.mp3"); # Creates a new object called $mp3_file. $mp3_file->print_tag(); # calls subroutine print_tag() on the file the $mp3_file object is working on (filename.mp3) if($mp3_file->got_tag()) { # calls subroutine got_tag(), which will return 1 if the tag exists, 0 if not. $mp3_file->set_title($title); # calls subroutine set_title(), which will set the title to the value $title. In normal practice, you probably would have parsed out of the filename $save_status = $mp3_file->save(); # calls subroutine save(), committing your changes. }