Fractal structures or geometries currently play a key role in all models for natural and industrial processes that exhibit the formation of rough surfaces and interfaces. Computer simulations, analytical theories and experiments have led to signiï¬cant advances in modeling these phenomena across wild media. Many problems coming from engineering, physics or biology are characterized by both the presence of diï¬erent temporal and spatial scales and the presence of contacts among diï¬erent components through (irregular) interfaces that often connect media with diï¬erent characteristics. This work is devoted to collecting new results on fractal applications in engineering from both theoretical and numerical perspectives. The book is addressed to researchers in the field.