This book addresses the possibilities and challenges in mimicking biological membranes and creating membrane-based sensor and separation devices. It covers recent advances in developing biomimetic membranes for technological applications with a focus on the use of integral membrane protein mediated transport. It describes the fundamentals of biosensing as well as separation and shows how the two processes work together in biological systems. The book provides an overview of the current state of the art, points to areas that need further investigation and anticipates future directions in the field. Biomimetics is a truly cross-disciplinary approach and this is exemplified by the challenges in mimicking osmotic processes as they occur in nature using aquaporin protein water channels as central building blocks. In the development of a biomimetic sensor/separation technology, both channel and carrier proteins are important and examples of how these may be reconstituted and controlled in biomimetic membranes are presented. Also new developments in our understanding of the reciprocal coupling between the material properties of the biomimetic matrix and the embedded proteins are discussed.  The basic concepts of membrane barrier properties are introduced and discussed in terms of lipid and polymer based membranes. Once a given protein is reconstituted in its final host biomimetic matrix, its stability needs to be maintained and controlled and the challenges associated with insertion and stabilization of alpha-helical bundle proteins are exemplified with aquaporin and ion channels as well as sodium-potassium ATPase proteins. The concept of multi-scale modeling is introduced and exemplified by the use of molecular dynamics, dissipative particle dynamics, and computational fluid dynamics simulations illustrating the issues involved in developing and describing biomimetic systems in a wide range of time and length scales. Scalability is a general issue for all nano-inspired technology developments and many biomimetic membrane applications require that the device can be used in the macroscopic realm. This challenge is addressed here in the context of fabricating biomimetic components, membrane arrays, and compartmentalized systems together with the challenges related to microfluidic design strategies for biomimetic device developments.