This paper reports the pilot phase of a three-year project, `Public perceptions of biotechnology', conducted in Perth, Western Australia. The purposes of this pilot investigation were (1) to develop a computer-based method for investigating public perceptions of biotechnology, and (2) to report the perceptions of four `interested publics' about the Flavr Savr™/MacGregor's® tomato, a genetically engineered tomato. By `interested publics' we mean members of groups who are not experts in the field, but have an interest because of their membership of the group. We developed a computer-based database of information about this tomato to stimulate, in interviews, respondents' articulation of their knowledge and perceptions of biotechnology. The database was a multimedia package, based on a HyperCard stack on a Macintosh PowerBook 180C, with information about the tomato in ten different categories. The data suggest that our methodology has the potential to provide a fruitful approach to exploring the background knowledges and perceptions of different publics.