Packages that require other packages - How?

Dear list,

The help page for library/require contains the following paragraph in
the section "Packages that require other packages":

     The source code for a package that requires one or more other
     packages should have a call to 'require', preferably near the
     beginning of the source, and of course before any code that uses
     functions, classes or methods from the other package. 

Now, I'm being very dense today, but I don't know where to put such a
call to require.

My package has added methods for a generic function supplied by another
package. I have listed this package in the Depends field in my
DESCRIPTION.

What do I need to do to have the package that my package depends on be
attached when I call library or require to attach my package?

Apologies for being dense...

Thanks,

G

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Gavin Simpson                     [T] +44 (0)20 7679 5522
ENSIS Research Fellow             [F] +44 (0)20 7679 7565
ENSIS Ltd. & ECRC                 [E] gavin.simpsonATNOSPAMucl.ac.uk
UCL Department of Geography       [W] http://www.ucl.ac.uk/~ucfagls/cv/
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