“…These challenges arose in the 1990s after TNCs experienced legitimacy crises due to extensive NGO and union campaigns and various media 'scandals' related to the working conditions at their suppliers' factories (Frenkel, 2001;van Tulder and Kolk, 2001;Roberts, 2003;Frenkel and Kim, 2004). In response to the criticism, TNCs started to extend their responsibility for workers' rights at their suppliers' factories in developing countries (Emmelhainz and Adams, 1999;Kolk and van Tulder, 2002;Sethi, 2002;Radin, 2004). The main actors involved in specifying and defining this extended sense of responsibility were TNCs, NGOs active in promoting workers' rights, and labour/trade unions (e.g., Christmann and Taylor, 2002;Frenkel and Scott, 2002;Sullivan, 2003;Frenkel and Kim, 2004;Prieto and Quinteros, 2004).…”