**1. Introduction**

The fields of ecology, evolution, and conservation are being transformed by novel resources and techniques in the biological sciences. One of these, DNA barcoding, has now realized its potential for the research community. Since the concept of DNA barcodes was first introduced in 2003 [1], tens of millions of barcode sequences have been made publicly available in reference databases for comparative research applications across the Tree of Life (Table 1). The growth of DNA barcode data in public repositories has been driven by several factors, including advances in sequencing technology, novel database managemen<sup>t</sup> and other computational software, and the expansion of national and international consortia that support DNA barcode sequencing. Recent reviews have highlighted the growth of DNA barcode applications for phylogenetics and taxonomy (e.g., [2]). Other overviews sugges<sup>t</sup> that DNA barcoding is a resilient field that will continue to grow as sequence databases are enriched, throughput expands, and automation provides an ever-expanding user-community with increased accessibility to DNA barcodes, as reported by [3]. This review highlights the advances and applications in DNA barcode sequencing that have been leveraged for novel research in ecology, evolution, and conservation.
