 The producers of these shows developed them using a variant on the CTW model, a flexible model of production based upon the experiences of the creators and producers of the US show. The model consisted of the combination of producers and researchers working together on the show, the development of a unique curriculum, and extensive test screening of the shows. The shows came to be called co-productions, and they contained original sets, characters, and curriculum goals. Different co-productions were produced, depending upon each country's needs and resources. They included both dubbed versions of the American show and versions created, developed, and produced in each country that reflected their needs, educational priorities, and culture. For example, the first HIV-positive Muppet, Kami, from the South African co-production Takalani Sesame was created in 2003 to address the epidemic of AIDS in South Africa, and was met with controversy in the US. By 2006, there were 20 co-productions in countries all over the world. In 2001, there were more than 120 million viewers of all international versions of Sesame Street, and by the US show's 40th anniversary in 2009, they were seen in more than 140 countries.
