Firesetting is a common behavior that is frequently encountered by forensic mental health experts when consulting on criminal and civil legal cases. Despite its prevalence, minimal attention has been paid in the literature to conducting firesetting-related forensic evaluations. In this article, we discuss the differences in the behavior of firesetting, the crime of arson, and the diagnosis of pyromania. The literature on adult firesetter characteristics, classification systems, recidivism, and treatment is reviewed. Several types of common criminal and civil firesetting-related evaluations referred to forensic mental health experts are discussed, along with case examples illustrating how the courts have approached such assessments. To our knowledge, this article is the first in 20 years to address firesetting-related forensic evaluations within the psychiatry literature. It also represents the first comprehensive discussion of civil evaluations related to firesetting.