The following methods are basically method \u201cA\u201d of Zillig et al. (1994) and were described recently in detail by Prangishvili (2006). These methods consist of enrichment cultures followed by host isolation and screening for virus production in both these isolates and enrichment cultures. These techniques are very similar to those used for bacteriophages, with the major exception being the extreme growth conditions (80\u02daC, pH 3).This is a protocol from: Stedman, K. M., K. Porter, and M. L. Dyall-Smith. 2010. Chapter 6: The isolation of viruses infecting Archaea. Manual of Aquatic Viral Ecology. Waco, TX:American Society of Limnology and Oceanography. doi:10.4319\/mave.2010.978-0-9845591-0-7Please see the published manuscript for additional information.