Plastic and reconstructive surgery is a branch of surgery that specialises in restoring form and function to damaged or missing tissues and skin. The causes of such defects are usually related to surgery, injury, illness or congenital abnormality. This rapidly evolving specialty is based upon the exploitation of key principles of anatomy, physiology, pathology and surgery. Mastery of these principles as well as the acquisition of sound surgical technique enables plastic surgeons to constantly adapt to the wide variety of individual cases they face and provide functional and aesthetic solutions. Comprehensively describing and explaining all of the principles of plastic and reconstructive surgery would require far more space and time than can be afforded in a single chapter. This chapter will therefore focus on key principles that will allow non-specialists to understand the fundamentals of this specialty. The first section concentrates on the basic sciences of skin anatomy and the pathology of wound healing relevant to plastic surgery. The second section will evaluate practical plastic surgery principles used every day in clinical and operative practice. Once completed, the reader should be well equipped to understand more sophisticated concepts conveyed in the literature.