Protecting workbooks

Hi Lesley, Thank you for your post, in answer to your question, there are two options open to you; the first is to protect your workbook against changes to the Structure which you can access from the Menu option Tool>Protection and choosing the Protect Workbook option you will be given two tick boxes one for Structure and one for Windows, you can apply a password at this point.
The second is to apply a password protection to open the Workbook, this can be accessed from the File>Save As option, Click the little drop down arrow next to the Tools button and choose the option General Options, in the dialog box that appears you can set a password to open and/or modify the Workbook. This option is also available under the
Menu option Tools>Options and under the tab for Security you can set the same password options. I hope that answers your question, best regards Pete.