However, it is encouraging to observe that the majority of the companies that
do obtain assurance have independent external assurance (30 percent) as opposed to internal assurance (5 percent), thus adding to the credibility of their sustainability
information and disclosures. This is supported by the study performed by Rea (2009,
p. 16) regarding South African assurance practices, which indicated that 30 percent of sustainability reports were found to be assured by third parties in 2007. These
findings, namely that the majority (83.33 percent) of independent assurance on
sustainability information is provided by audit firms, are also further consistent with the
literature as discussed in Sections 1 and 3.