How to list all posts in one catagory in one page

I have been using

<?php if (is_page('41')) { ?>
<div id="directory">
<?php wp_list_pages('child_of=41&sort_column=post_title&title_li='); ?>
</div>
<?php } ?>

Is there an easy way of doing this with a POST category? For Example. I have a post category called “Promotions” with an ID=5.

Thanks for any help in advance.