Viruses are ubiquitous structures that can infect cells from various forms of life. Determining viral community structure and function in association with health and disease is of increasing interest. This field, also known as viral metagenomics, will likely continue to expand and be applied in a variety of areas ranging from discovery to surveillance, and will rely heavily upon the continued development of reference materials, collection devices, analysis pipelines and databases. Viral metagenomics information could potentially translate into biological, environmental and clinical applications, including the rapid sequence identification of pathogenic viruses in various sample typ¬¬es, and determining potential known and unknown virus-host relationships. However, viral metagenomic approaches often lack appropriate reference materials to enable cross-study comparisons and assess potential biases which can be introduced at the various stages of collection, storage, processing, and sequence analysis. As the field of viral metagenomics expands and standardizes, results will continue to translate into diverse applications.