excel training onsite - Comparind data

Thanks Amanda..,

The spreadsheets I am talking about runs the data of thousands of customers and so it is difficult to compare each customer name using Ctrl + F. It is equally difficult to compare them by minimising to display side-by-side in the screen as, apart from 'customer name' other data in the spreadsheets are very different.

Is there a way to tell 'Excel' to run through both the spreadsheets, compare the data on 'Customer Name@ column and report back saying, 'this is the list of customers present in both the spread-sheets'

Thanks and regards,
Fazil