Hi,

your Master page be it MasterPage.master could expose a property which wraps to the Label's (Label1) Text property.

Public Property LabelText() As String
        Get
            Return Label1.Text
        End Get
        Set(ByVal value As String)
            Label1.Text = value
        End Set
    End Property

Content page would then need to have @MasterType directive so that the property could be accessed via Master in a typed manner.

<%@ Page Language="VB" MasterPageFile="~/MasterPage.master" AutoEventWireup="false" CodeFile="Default2.aspx.vb" Inherits="Default2" title="Untitled Page" %>

<%@ MasterType VirtualPath="~/MasterPage.master" %>

Then, code on content page could just do:

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        If Not Page.IsPostBack Then
            Master.LabelText = "This text goes to the Label on master page"
        End If
    End Sub