Linking workbooks

How can I link the cells in both workbooks, so the changes in "A" will be reflected in "B" and the changes in "B" will be reflected in "A"?

Let's say in Book1 you want Sheet1!A1 to equal the same cell in sheet1 of Book2. In Book1, sheet1, cell A1, use this:

=[Book2]Sheet1!$A$1

Book1 will reflect the changes made in Book2 for all linked cells.

Is this what you are after?