If highlighting rows means selecting entire rows, I think this would be
enough.

MsgBox Intersect(Selection, Columns(1)).Count

If not entire rows, then

MsgBox Intersect(Selection.EntireRow, Columns(1)).Count

Keiji

Rick Rothstein wrote:
By "highlighting", do you mean "selecting"? If so, then give this macro
a try (it will handle both contiguous and non contiguous selections)...

Sub CountRowsInSelection()
Dim A As Range, U As Range
For Each A In Selection.Areas
If U Is Nothing Then
Set U = A.EntireRow
Else
Set U = Union(U, A.EntireRow)
End If
Next
MsgBox Intersect(U, Columns(1)).Count
End Sub