6 answers
Like I said in my earlier post there are several different ways to make a field required.
You can create a Validation Rule:
https://na2.salesforce.com/help/doc/en/salesforce_useful_validation_formulas.pdf
or you can do it using the Page Layout Editor or Field Accessability Settings:
https://na2.salesforce.com/help/doc/en/salesforce_pagelayouts_cheatsheet.pdf
A lot of the answers to your recent posts can also be found in the Online Help & Training:
https://na2.salesforce.com/help/doc/user_ed.jsp?loc=help
