Here are two examples of what I am doing.

One instance I am using a value which is the customer name. It is on the first sheet with the customer address and such. The last sheet is a letter that goes to the customer. I need to take the customer name from the 1st sheet and apply it to the last sheet's letter.

A second example is taking a value from a chart on the second tab and plugging that value into a forumula within the 3rd tab.