// First the Interface needs to be defined in your namespace somewhere: public interface IMyInterface { string BasePath { get; set; } } // Then, your two classes need to implement that Interface public class JdaBusinessWebPage : mmBusinessWebPage, IMyInterface { private string m_BasePath; public string BasePath { get { //whatever code you need for this} set { //whatever code you need for this} } } public class JdaUserLogin : mmBaseUserLogin, IMyInterface { private string m_BasePath; public string BasePath { get { //whatever code you need for this} set { //whatever code you need for this} } } // Then, you can cast to the Interface to access the property string MyBasePath = ((IMyInteface)this.Page).BasePath;~~Bonnie