Hi,

Probably not the most effecient but try this

Sub marine()
Application.ScreenUpdating = False
Application.Calculation = xlCalculationManual
Dim MyRange1 As Range
Dim MyRange2 As Range
x = 6
Set MyRange1 = Range("B6:B10000")
Set MyRange2 = Range("I6:I10000")
For Each c In MyRange1.Cells
For Each d In MyRange2.Cells
If c.Value = d.Value Then
Cells(x, 19).Value = c.Value
x = x + 1
Exit For
End If
Next
Next
Application.ScreenUpdating = True
Application.Calculation = xlCalculationAutomatic
End Sub

Mike

"J.W. Aldridge" wrote:

I have a string of data (numbers) starting in B6:B10000 and another
in
I6:I10000..

I need a code to search both strings and return any numbers that
appeared in both list. This list of duplicated numbers should start in
S6.