Preparation of samples is a critical stage in the analytical procedure that has benefited significantly from advances in green chemistry. Green sample preparation entails eliminating the use of toxic solvents and minimizing energy requirements throughout the procedure. This chapter gives an overview of green extraction processes, as well as a brief introduction to their theoretical foundations and a look at how they can be used in the fields of analytical and bioanalytical research, with a special focus on food, environmental, and biological matrices.