There are two important research areas in hazmat transportation that are widely studied in the literature: risk assessment and shipment planning. In the risk assessment area, important issues include measurement of accident probabilities and consequences in hazmat transport. Example works in the risk assessment area include modeling risk probability distribution over given areas, considering hazmat types and transport modes, and environmental conditions. The first half of this handbook covers the two fields of risk assessment and shipment planning, while the second half of this handbook provides useful models and insights on other important issues including location problems for undesirable facilities, network interdiction, terrorist attack, and evacuation.