Large wildland fires are complex, costly events influenced by a vast array of physical, climatic, and social factors. Changing climate, fuel buildup due to past suppression, and increasing populations in the wildland-urban interface have all been blamed for the extreme fire seasons and rising suppression expenditures of recent years. With each high-cost year comes a multitude of fire cost reviews, suppression cost studies by federal oversight agencies, and new rules and regulations focused on containing or reducing suppression costs. However, largely ignored in many of these inquiries are the human factors and pressures outside (external to) the influence of the incident team managing a fire that are contributing to the problem. This article presents an in-depth examination of some external human factors that affect incident management team (IMT) decisionmaking and influence suppression costs. Data were collected during 2004 and 2005 through 48 in-depth interviews with IMT command and general staff members representative of each Geographic Area Coordination Center, all federal agencies, and many state agencies whose employees serve on teams. External human factors identified include risk management; interaction with agency administrators; policies, regulations, and rules; resource availability; and social-political pressure. Inattention to these factors can result in policies that adversely affect IMTs charged with managing highly volatile events in a safe, timely, and cost-efficient manner.