What is wrong with this code?

What is wrong with my code, I get an error trying to implement the interface?

Imports Microsoft.VisualBasic

Public Interface ISelectedPublisher
    'ID of the selected publisher

    ReadOnly Property SeletedPublisherID() As String

End Interface 'ISelectedPublisher

Partial Public Class UCPublishers
    Inherits System.Web.UI.UserControl
    Implements ISelectedPublisher

    'Get the Selected Value from the DropDownList that holds Publishers
    Public ReadOnly Property SeletedPublisherID() As String
        Get
            Return cmbPubs.SelectedValue.ToString
        End Get
    End Property

    <ConnectionProvider("SelectedPublisher", "SelectedPublisher")> _
    Public Function GetSelectedPublisher() As ISelectedPublisher
        Return Me
    End Function
End Class

Thanks,
Mike