For historical reasons, we need to expose string constants in .NET through COM interface. We managed to expose ENUM but we can't find a way to expose string const. We try the following code : <ComClass(ComClass1.ClassId, ComClass1.InterfaceId, ComClass1.EventsId)> _ Public Class ComClass1 #Region "COM GUIDs" ' These GUIDs provide the COM identity for this class ' and its COM interfaces. If you change them, existing ' clients will no longer be able to access the class. Public Const ClassId As String = "608c6545-977e-4260-a3cf-11545c82906a" Public Const InterfaceId As String = "12b8a6c7-e7f6-4022-becd-2efd8b3a756e" Public Const EventsId As String = "05a2856f-d877-4673-8ea8-20f5a9f268d5" #End Region ' A creatable COM class must have a Public Sub New() ' with no parameters, otherwise, the class will not be ' registered in the COM registry and cannot be created ' via CreateObject. Public Sub New() MyBase.New() End Sub Public Const chaine As String = "TEST" Public Sub Method() End Sub End Class But when we look on the OLE object viewer, we only see the method. See ScreenShot: screenshot of OLE viewer Anyone have an idea ? Thanks,