Installing SMO
If you want to develop an application that uses SQL Server Management Objects (SMO), you should select the Client Tools SDK when you install SQL Server. To install the Client Tooks SDK without installing SQL Server, install Shared Management Objects from the SQL Server 2008 R2 feature pack. If you want to ensure that SQL Server Management Objects is installed on a computer that will run your application, you can use the Shared Management Objects .msi in the feature pack.
By default, the SMO assemblies are installed in the C:\Program Files\Microsoft SQL Server\100\SDK\Assemblies\ directory.