Prepare a series of questions. Use this list of questions for every exit interview, the Houston Chronicle suggests. Much like in a job interview situation, asking off-the-cuff questions can get you in trouble -- though there is a thin line between asking a natural follow-up question and veering completely off script.
Ask the employee's permission. Not every employee wants to go through an exit interview, and there are no laws that require them. So you may want to explain the purpose of an exit interview and tell the employee how the company will use the information it obtains. You may also want to assure the employee that her responses will be kept both anonymous and confidential. If you do, make sure this is the case.
Remain neutral. You want to avoid asking leading questions during the interview. You should stick with open-ended questions, and give the employee time to think about her response. And if employees are leaving for personal or health-related reasons, you do not want to ask too many detailed questions. This may violate privacy rights of the employee.
Reassure the employee. Even if you already told the employee that nothing said during the interview will be used against her, remind her again. This will encourage the employee to be more candid as she is not afraid of burning bridges.
Thank the employee. You will want to conclude the exit interview on a positive note. Let the employee know that you are thankful for their service. You may also want to go over final employment matters at this time like explaining payout of accrued vacation, COBRA, etc. And if you're being forced to lay people off, it may be helpful to print out copies of FindLaw's free Guide to Unemployment Insurance and hand them out as a resource.