Next-generation sequencing (NGS) involves the laying down of the sequence of the entire genome or exome at one time. This technique is expected to become one of the approaches in diagnostic testing. The genetically determined vulnerability of individuals to disorder and their response to treatment can be determined at one go. However, this gives rise to ethical and legal questions, particularly in the area of the protection of patient privacy. These questions include provision of information to the patient about the DNA investigation and the chance of incidental findings, feedback to the patient concerning incidental findings and the storage and reuse of the genetic information. It is important to begin discussion of the legal and ethical consequences of NGS investigations at an early stage. This article may be the stimulus for this discussion.