You may use the BackgroundWorker class.
Imports System.ComponentModel
Friend WithEvents BW As BackgroundWorker
Sub Start()
Dim task As Object = "Hello, World!"
BW = New BackgroundWorker
BW.RunWorkerAsync(task)
End Sub
Private Sub BW_DoWork(sender As Object, e As DoWorkEventArgs) Handles BW.DoWork
e.Result = e.Argument
End Sub
Private Sub BW_RunWorkerCompleted(sender As Object, e As RunWorkerCompletedEventArgs) Handles BW.RunWorkerCompleted
MsgBox(e.Result)
End Sub