This second editionField Manual of Techniques in Invertebrate Pathology provides updated information and includes two additional chapters and 12 new contributors. The 40 chapters in 10 sections provide the tools required for planning experiments with entomopathogens and their implementation in the field. The basic tools include chapters on the theory and practice of application of microbial control agents (MCAs) (Section I), statistical considerations in the design of experiments (Section II), and three chapters on application equipment and strategies (Section III). Section IV includes individual chapters on the major pathogen groups and special considerations for their evaluation under field conditions. Twenty-three chapters on the application and evaluation of MCAs in a wide variety of agricultural, forest, domestic and aquatic habitats comprise Section VII. Several of these chapters include supplementary techniques and media for conducting follow up laboratory studies for confirmation of infection, determination of persistence, etc. The three final chapters include: special consideration for evaluation of Bt transgenic plants (Section VIII); resistance to insect pathogens and strategies to manage resistance (Section IX); and guidelines for evaluating effects of MCAs on nontarget organisms (Section X). Due to uncertainty regarding the future availability of organophosphate and other conventional chemical insecticides, MCAs will play increasingly important roles in IPM. The Field Manual will provide researchers and IPM practitioners with techniques and practical guidance for the study and optimal use of MCAs in a variety of settings.