cycling through values in a MS Access list box

You can do a For loop to examine each row in the listbox, and do whatever with the rows which are selected. In this example, I display the second column from selected items in the lstLocations listbox. (Column numbering starts with zero.)

Private Sub cmdShowSelections_Click()
    Dim lngRow As Long
    Dim strMsg As String

    With Me.lstLocations
        For lngRow = 0 To .ListCount - 1
            If .Selected(lngRow) Then
                strMsg = strMsg & ", " & .Column(1, lngRow)
            End If
        Next lngRow
    End With

    ' strip off leading comma and space
    If Len(strMsg) > 2 Then
        strMsg = Mid(strMsg, 3)
    End If
    MsgBox strMsg
End Sub

Note I assumed you want the selected items from the list box. If you want all items, selected or not, you could use .ItemData as @DavidRelihan suggested. However, in that case, you could get them from the listbox .RowSource instead.

Here is how you iterate through the ListBox:

Dim i as Integer

For i = 0 to Me.ListBoxName.ListCount -1
   'Access each item with 
   'Me.ListBoxName.ItemData(i)
Next i

If working with a listbox in Access I like to capture the listbox recordset and loop through it. Perhaps because I find DAO recordset objects easy to work with.

I'd do something like:

Dim Rst as DAO.Recordset
Set Rst = lbxYourListboxObj.Recordset
'test to assure that there are records
If Rst.EOF then
     'some error handling
end if
'I'm just paranoid so I always do this
Rst.MoveFirst
'iterate through list
Do Until Rst.EOF
    'do something for each record
    'it is nice and convenient to be able to reference the field names directly too!
    debug.print Rst!Field1.name,Rst!Field1.value
    Rst.MoveNext
Loop