The advent of viral marketing in South Africa has been supply focused and retail operators did not realise the importance of including customers' views during the creation of viral marketing strategies. Failure of these stores to incorporate customers' views during the crafting of viral marketing strategies, leads to ineffective viral advertising campaigns, product boycott and decrease in sales. Given the constant change in consumer needs and expectations, an understanding of customers' opinions towards viral marketing strategies adopted by a retail store in Johannesburg, has become a remarkable strategy to gain a competitive advantage. For that reason, it is important for retail stores to understand their customers' perceptions of viral marketing strategies. Based on this background, the purpose of this study was twofold: i) to assess customers' perceptions of viral marketing strategies, and ii) investigate how viral marketing strategies influence customers' buying behavioural intentions. A descriptive case study approach was conducted. A quantitative methodology, through which a structured questionnaire was also used to collect data from a sample of at least 172 customers at outlets of a retail store in Johannesburg. SPSS was utilised to conduct descriptive and multivariate analyses including factor analysis, correlations, and regression analyses. Results indicated that customers had negative perceptions towards viral marketing strategies tested. In addition, all the four predictor variables (informativeness, entertainment, irritation and source credibility) were found to be positively correlated to customer buying behavioural intentions. Recommendations and gaps for further research are also presented within the context of viral marketing theory.