Stress Concentration at the Notch Root.- Stress Intensification at the Crack Tip.- Stress Intensification at the Vertex of a Re-entrant Corner.- Energy Approach to Fracture Mechanics.- Mixed-mode Crack Propagation.- Nonlinear Crack Models.- Size-scale Transition from Ductile to Brittle Failure.- Mechanical Behaviour of Reinforced Elements.- Fractal Scaling of Fracture Energy, Tensile Strength, and Ultimate Strain.- Fractional Calculus Applied to Fractal Media and Nonlocal Continua.- Fragmentation, Comminution, Drilling, and Wear.- Nonlinear and Chaotic Behaviour in the Vibration of Cracked Bodies.- Debonding and Decohesion at the Interface Between Dissimilar Media.- Scaling in Fatigue and Creep Mechanisms.- Acoustic Emission and Critical Phenomena in Structural Elements and Earth Crust.