Full archive listing?

I wish to show my complete archive for a certain criteria (e.g., August 2007 or by a category), yet it only displays 10 posts because I believe that’s how many posts are set to be displayed in WordPress’ options. How can I remove that limit specifically for the archive and display the full thing?

For instance, my site says that I have 20 posts for August 2007, but I only see 10 on its archive page.

This seems like it should have an easy solution so I don’t really want a plugin to solve this. I don’t think I need one.