That will not work.  Here is how it is done:
Use the Survey_ID control's Before Update event.  It can be canceled and
when it is, the focus does not move.

Private Sub Survery_ID_BeforeUpdate(Cancel As Integer)

   If Trim(Nz(Me.Survery_ID, vbNullString)) & vbNullString = vbNullString
Then
       MsgBox "A Value is required"
       Cancel = True
   End If

End Sub

this part:
Trim(Nz(Me.Survery_ID, vbNullString)) & vbNullString

Will catch not only a Null, but cases where a user has accidentily put a
space in the control.

Hi Jeff,

rather than the LostFocus event, use the control BeforeUpdate event and
CANCEL the change ... better yet, use the FORM BeforeUpdate event to
ensure that all required data is filled before a record (new or changed)
is saved

what is Survey_ID?  something that the user is supposed to fill out
before a record is saved?

to validate a record and prevent it from being saved, put code in the
form BeforeUpdate event

'~~~~~~~~~~~~~~~~~~~~~~~~~~
   '----------------- make sure all required data is filled out

   'make sure Survey_ID is filled out
   If IsNull(me.Survey_ID) then

      'if it is not filled out, then move the focus to that control
      me.Survey_ID.setFocus

      'give the user a message
      msgbox "You must enter the Survey ID",,"Missing Data"

      'don't save the record yet
      Cancel = true

      'quit checking and give them a chance to fill it out
      exit sub
   end if
'~~~~~~~~~~~~~~~~~~~~~~~~~~

Warm Regards,
Crystal

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