This book explores the most recent advanced research activities in the field of polymers and composites derived from renewable, both plant and marine, resources. It covers different components of composite materials including emerging polymeric materials (from elastomers to rigid thermosets) as well as nanosized biosourced fillers extracted from biomass. These biopolymeric nano-assemblies have garnered in the materials community a tremendous level of attention that does not appear to be waning. Biopolymers derived from the different biomass components such as oils, carbohydrates and phenolic substrates are also discussed. In this regard, new polymeric materials obtained from simple modification of the renewable polymers or totally synthesized from building blocks derived from renewable resources using different routes are included. Demanding applications for such composite materials in various fields as well as the environmental impact engendered by their intensive production are examined in the last part of the book.