Nellie works for a large Fortune 500 company. She heads the information systems department and works closely with the accounting department. The company works with many associates. They have many buyer and supplier companies they work with. Nellie knows a lot about the database systems and accounting practices in the company. She even works closely with buyers and suppliers to create data communication lines. Recently, Nellie has become concerned about the integrity and reliability of the accounting and information systems. The company has grown to a point where she cannot manage or supervise all the activities performed in these areas. What proactive steps can Nellie take to ensure systems and accounting integrity and prevent fraudulent behavior?