>If you already have SQL 2008 Express installed on a machine but no Reporting Services, can the Reporting Services component be downloaded and installed or does it require download of the entire SQL Express plus RS, and then a reinstall over or in addition to the existing SQL Express component?
>
>Thanks,
>Bill

If you already installed SQL 2008 Express with Advanced Services, you can additionally install Reporting Services (just add to the existing installation).

Keep in mind that SE has some limitations when it comes to RS. I remember I tried once RS from SE and there were features I can not use.