Bark, the boundary between trees and their environment, comprises about 10–20% of their total volume. Approximately 4 million m³ of bark is collected annually in German sawmills. Only a small part of this bark is used as an end product; the majority is burned wet in sawmillsdue to reduced economic interest, a lack of production facilities and a lack of knowledge about other uses, as compared to wood. Reasons for this are related to the high variability of bark properties between and among tree species and even within one tree. The aim of this thesis is to understand the material properties of selected types of bark through scientific and design methods and to explore processing possibilities that lead to longer lifecycle applications and cascade uses. In the beginning of this thesis, bark from species endemic to Brandenburg (northeast Germany), Scots pine (Pinus sylvestris,L.), English oak (Quercus Robur,L.), European larch (Larixdecidua, Mill.) and European white birch (Betula pendula,Roth), were manually peeled to obtain large pieces of bark, which were afterwards air dried and modified with a variety of processing techniques. In the first procedure, two or more pieces of peeled bark were placed crosswise, the rhytidome (outer bark) facing each other, and hot pressed into panels. First, mechanical tests showed that bending stiffness, bending strength and transverse tensile strength are similar to wood-based panels such as particle board. A strong effect of the fiber orientation on the bending properties was detected. Experiments on raw bark with specifically adjusted water content during the pressing process showed effects on swelling behavior and mechanical properties. In the transverse direction, large swelling was observed with increasing relative humidity. This swelling remained permanent, even upon drying, for some bark. However, bark panels appeared smooth after the pressing process, with surface roughness similar to solid sanded wood. This surface quality and their machinability with conventional processing methods, such as sawing and computerized numerical control milling gives them potential furniture and paneling applications. Additionally, densification into more complex forms were realized with oak bark. In a second approach, a procedure was developed to preserve flexibility and to keep the texture and color of freshly peeled bark. The presented experiments show that it is possible toflexibilize mirror pine bark and the phloem of larch bark, but oak and birch could not be flexibilized. The successful flexibilization of mirror pine bark is presumed to be based on the high proportion of conductive phloem. The effect of glycerol water solutions on the mechanical properties of bark were quantified by performing tensile tests. Interestingly, bark sample streated with glycerol showed improved flexibility and stress at failure compared to wet bark. To obtain more information about the influence of glycerol water treatment on mechanical properties of pine bark, tensile tests were performed with adult spruce wood and compression wood. A remarkable difference between bark and wood is that the glycerol treatment of wood does not lead to larger tensile strain compared to water immersion. This finding suggests that pine mirror bark has a high cellulose microfibril angle (like compressed wood). Comparative tensile tests with two different sets of cowhide leather samples showed that flexible pine bark is more than five times stiffer than leather when stressed along the graineven though the leather and bark samples showed similar haptic feel, flexibility and processing possibilities. The third procedure explores possibilities of using bark ashes – a final waste product of the wood processing industry. Tree bark is known for its different chemical composition compared to wood. Selected bark ashes were analyzed by inductively coupled plasma (ICP) mass spectrometry and then mixed with transparent porcelain glazes and fired. The bark ash glazes gave colored glazed bowls, with colors characteristic of the elements potassium and manganese: beige, yellow, rose and deep dark brown. Calcium acted as a flux and produced net-like surface patterns in the spruce ash glaze. Finally, the processes developed during the thesis were successfully transferred into design prototypes. By using glycerol, it was possible to flexibilize pine bark, allowing for different textile design objects. Flexibilized pine bark – based on its protective function for trees – was applied to fashion in the form of a jacket, and further optimized through weaving techniques. In addition, shoes with robinia bark soles were manufactured, highlighting further applications for tree bark. Optimized processing techniques open up the possibility of larger-scale flexibilized bark applications in architecture. To reflect the potential of bark in architectural applications, an installation which people could stand inside and experience being completely surrounded by bark was built. In form of a hollow walk-in sphere, three-dimensional fabrication – largely free of the geometric limitations of the starting material (bark) – was demonstrated. The abstract form of a sphere leaves enough space for free associations and encourages communication and exchange about bark as a possible future design material.