We provide commentary on selected methodologies of risk assessment and management for safety and security programs in critical infrastructure. The methodologies include risk identification, risk filtering and ranking, synthesizing quantitative and qualitative evidence of risk, risk-based project selection, and risk-based combinatorial optimization. The cited applications include: roadway lighting and guardrail, bridge security, airport improvements, port improvements, transit improvements, hurricane impacts to transportation systems, water distribution systems, telecommunications systems, flood levees, river navigation, and military peacekeeping.