The offer, interpretation and consequences of genetic testing raise complex issues for counsellors, patients and families. These have received much attention but one important area that is little understood is how patients come to a decision about taking a genetic test (or not). Much is known about how people retrospectively describe their decision-making process and the effects of genetic knowledge on themselves and their families but less is known about how counsellors discuss the implications of taking genetic tests with patients and much less is known about how people make their decisions. By following people during this process, we aim to improve our understanding of how their thinking develops and the other people and factors that influence this. This is particularly important at a time when ever more information about genetics is communicated online, in newspapers and in popular culture, and as families gain more experience of dealing with genetics services. Our proposal is to focus on cases where the decision to take a genetic test is for the patient to make, supported by genetic counselling but without a clinical recommendation, as the genetic test result is of limited clinical utility. Using multiple methods, we propose to examine the communicative context in which patients make their decisions and how their thinking unfolds in this context. We will focus on the experiences of three groups of patients: patients seeking predictive genetic testing for a neuro-degenerative condition (e.g. Huntington's Disease, HD); patients seeking predictive genetic testing for a condition where testing has little utility or it is deferred; and prospective parents seeking pre-natal genetic testing, either for a known familial risk or following an antenatal foetal anomaly ultrasound scan. These cases will illuminate different experiences that patients may have in deciding on a genetic test. The case of HD will show how a patient settles on a decision to take a test knowing a 'bad' outcome foretells a future of impairment. The predictive test of little or deferred utility will mostly involve young adults and will illuminate the experience of wrestling with a decision in a formative period in life with no immediate clinical implications. Prospective parents working with the genetics service in light of a familial risk of a genetic condition will illuminate the importance of personal and family experience in the decision process, while those referred after an ultrasound anomaly scan will shed light on the experience of adjusting to unexpected information in a short period of time. In each case, patients and their families are faced with complex information about tests, testing pathways and potential outcomes. By following people as they make their decision we will observe the clinical encounters and the patients will gather information on their own thoughts, on what people are saying to them, and what other information they are seeking or interacting with. While fully aware of the need for great ethical sensitivity in this enquiry, we will document how genetic information from outside the clinic (as framed by scientists, marketers, journalists, charities and special interest groups) is brought into the clinic discussion and the patients' reports of their own thinking. The conversations between patients and counsellors in clinic are important to this process, but this conversation is increasingly relativized by rapidly evolving scientific insights and supplemented by outside perspectives. Combining insights from all involved will enable us to develop our understanding of how patients come to their decision, and the effect of outside ideas and framings on this process. Simultaneously, by comparing the thinking of the different groups of patients, we will gain insight into the effect of different experiences of time on this thinking, and explore whether and how these reflections might be facilitated by decision support tools.