Thanks for all your help. Lots of good stuff here. At the risk of appearing useless I may need some help with code provided by TedPride ( very cool BTW ).

sub remove {
    my ($p, $d) = @_;
    if ($d-- > 1) {
        remove($_, ($d)) for values %$p; # Had second decrement here
    }
    else {
        my %newhash;
        for (values %$p) {
            @newhash{keys %$_} = values %$_;
        }
        $_[0] = \%newhash;
    } 
}
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I've not seen one of these before. It's an hash but it looks like an array ie '@'

for (values %$p) {
            @newhash{keys %$_} = values %$_;
        }
        $_[0] = \%newhash;
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What is going on here then ? Checked out my cookbook etc but can't find a reference to this syntax. One other slight complication is the data can actually look like this;

$W={
    'A' => {
        'L' => {
            'D'=>99,
            'X'=>99,
              },
        'C' =>{
            'E'=>99
             },
          }, 
    'X' => {
        'Q'=>{
            'O'=>99,
            },
        'T'=>{
            'U'=>99,
            },
          }, 
        'W' => 99,
    };
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Now when we collapse level 2 ie LCQT I don't want to change the value for 'W'. So only drop values on the target level if they are HASH. So really it's a mix of H,HOH and HOHOH etc. Thanks again for your help. Jeff