Segregation of Duties IS a key component of effective internal control; 45 companies in our sample specifically disclose a material weakness in their segregation of duties. Assigning one person with two related functions increases the possibility of theft within the organization. For example, it is not wise to have one person authorize the payment of a vendor's invoice and also sign the check that pays the invoice. In addition to possible embezzlement, lack of segregation of duties might facilitate financial statement manipulation. Deficiencies in segregation of duties are sometimes, but not always, associated with an insufficient number of accounting staff