Exiting a Sub

Hi all, first I'll submit the code and then the problem:

Sub IndMthlyExistingMth_Udate()

Dim blnUpdate As Boolean
blnUpdate = Application.ScreenUpdating
Application.ScreenUpdating = False

'This Sub is used to run the updates on pre-existing updates.
Application.Run "SourceTransfer"
Application.Run "CleanDataReTransfer"
Application.Worksheets("IndMthly").Select
Application.ScreenUpdating = blnUpdate

End Sub

When I step into the "SourceTransfer" Sub, I have this code to make sure that there has been data inputted into the proper cell:

If ActiveCell.Value = "Paste Here" Then MsgBox ("There is no data in the ""Insert"" sheet.")
If ActiveCell.Value = "Paste Here" Then Exit Sub

If this happens, I want to exit the "IndMthlyExistingMth_Udate" Sub without carrying on to the next line, being:

Application.Run "CleanDataReTransfer"

I've tried some boolean tests but I cannot make it work once the "SourceTransfer" exits it's Sub. Any Suggestions?