This book presents detailed descriptions of the most relevant sorbent based and solvent-based microextraction techniques. The development of such miniaturised techniques is an important focus area in Green Analytical Chemistry as it allows for the reduction of toxic solvents and hazardous substances and decreases the complexity, cost, and time of analytical procedures. Numerous advances have been made in this field, and currently, there are a great number of microextraction techniques thanks to the development of novel materials such as nanomaterials and green solvents. This book provides an overview of the two main groups of microextractions, sorbent-based, and solvent-based. Each chapter focuses on the description of the technique fundamentals, the main applications, and the novel developments carried out in recent years written by a renowned expert or group of experts in the field. The main audience will be graduates, postgraduates, and researchers. It is also a useful resource for Master and Ph.D. students that are working in the development of sustainable extraction techniques