Although there is immense international support for consumer protection, the notion exists that consumer protection can only exist in developed countries with ample fiscal resources and expertise to properly act in the interest of consumers. This conception leaves consumers in emerging and transitional economies in a difficult position as these economies indeed generally lack sufficient funding and the required capacity to educate consumers on their rights. With the South African Consumer Protection Act that came into effect in 2011, South African consumers can now claim to be among the best protected consumers in the world. However, many consumers are still not aware of their consumer rights, and do not have the necessary knowledge to pursue redress when they are dissatisfied. The objective of this research was therefore to explore and describe the relationship between consumers’ knowledge of consumerism (consumer protection) and their consumer complaint behaviour (CCB) concerning their dissatisfaction with a technologically advanced product, in this case, a consumer electronic product. This study attempts to differentiate between subjective consumerism knowledge and objective consumerism knowledge and by extension the measures used. In addition, we explored and described the relationship between demographic variables and levels of subjective and objective consumerism knowledge as well as the combined effect of the two types of knowledge on CCB. The findings revealed that the respondents had a reasonable level of subjective consumerism knowledge relative to a low level of objective consumerism knowledge. No significant relationship was found between subjective consumerism knowledge and demographic variables. However, the factors of race, gender and level of income were related to objective knowledge. A higher level of subjective knowledge could be associated with public action. Respondents with reasonable levels of objective knowledge were also better equipped to take private and public action. CHAID (Chi‐Square Automatic Interaction Detection) analysis highlighted that a combination of subjective and objective knowledge was the best predictor of taking public action only and of taking both private and public complaint action. The study has implications for policy makers, consumer protection organisations, retailers and the individual consumer. Our approach to measuring knowledge of consumerism could possibly be applied in other emerging contexts where consumers generally lack awareness of consumer protection.