Helen, a business operations manager, was accused of writing numerous business checks to herself. Supposedly, she wanted to reimburse herself for various business expenses, for the back pay she was owed, and for payroll purposes. The investigation showed that she used company funds to pay for her personal mobile phone bill on 12 occasions. The bills totaled $3,617.08.

What internal controls do you think should have been in place to prevent this embezzlement?