Sequencing has progressed from a discovery tool in genomics and systems biology to a translational research tool and, within the last five or so years, an instrument of the clinical laboratory. Also referred to as post-Sanger sequencing, next-generation sequencing (NGS) uses massively parallel reactions to perform billions of short reads from sample nucleic acid populations. Expected to exceed $5 billion in market size within this decade, next-generation sequencers will be joined by even faster, smaller and less expensive third-generation sequencers able to be placed more widely in health care and industry.