vb.net sqlconnection err

Hi

i got the error

type is not defined: 'SqlConnection'

How to add a reference to Sql in VB.Net??

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
' Open a connection to the database.
Dim strConnection As String = _
"Data Source=192.168.0.1; Initial Catalog=Northwind;" _
& "Integrated Security=True"
Dim cn As SqlConnection = New SqlConnection(strConnection)
cn.Open()

' Set up a data set command object.
Dim strSelect As String = "SELECT * FROM Customers WHERE City = 'London'"
Dim dscmd As New SqlDataAdapter(strSelect, cn)

' Load a data set.
Dim ds As New DataSet()
dscmd.Fill(ds, "LondonCustomers")

' Close the connection.
cn.Close()

' Do something with the data set.
Dim dt As DataTable = ds.Tables.Item("LondonCustomers")
Dim rowCustomer As DataRow
For Each rowCustomer In dt.Rows
Response.Write(rowCustomer.Item("CompanyName"))
Next


End Sub

Thanks

Have you imported the System.Data namespace?