This series provides testing and informational guidelines for data to be submitted to support registration of Microbial Pest Control Agents (MPCAs). This series of guidelines (OPPTS 885) provides detailed information relating to the data requirements listed in section 158.740, including the conditions under which each data requirement is applicable, the standards for acceptable testing; the information that should be included in a test report; guidance on evaluation and reporting of data; and examples of protocols. In addition, scientific publications are cited in the guidelines to provide useful information for designing test protocols. Pesticides referred to as MPCAs include (but are not limited to) bacteria, algae, fungi, viruses, and protozoa as defined in 40 CFR 152.20. The guidelines apply to all MPCAs used as pesticides, including both those that are naturally occurring, and those that are strain-improved either by natural selection or by deliberate genetic manipulation.