The themes of this monograph include modern engineering problems of marine traffic engineering, focusing on what this discipline deals with: navigational safety assessment methods. These include: 

• criteria of assessing navigational safety in restricted areas,
• navigation risk, as a complex criterion of navigational safety assessment in waterway systems,
• models of navigation risk determination used worldwide,
• conditions of safe operation of ships on waterways determined by using navigation risk,
• minimum safe tug assistance on port waterways,
• navigation risk management in waterway systems with a description of a computer program for model-based tests of navigational safety on Southern Baltic waterways.