[3]. In other words, proper selection and optimisation of the sample preparation scheme are key aspects within the analytical process that can greatly affect the reliability and accuracy of the final results [4,5]. Conventional techniques, such as liquid–liquid extraction (LLE), solid–liquid extraction (SLE) and Soxhlet extraction, are still widely accepted and used for routine applications and/or for reference purposes. However, in recent years, some of these techniques have been revisited and upgraded versions, in which their most pressing shortcomings have been solved, are now available. The studies in this field have also led to the development of new faster and more powerful and/or versatile extraction and preconcentration techniques [6]. Thereby, in many instance, partial and even full hyphenation and automation of the analytical process, or at least of the several treatment steps, are now possible. In addition, sample preparation approaches that fulfil the goals of green analytical chemistry [7] are also available. For obvious reasons, the ideal situation would be the complete elimination of the sample preparation step from the analytical process. However, despite the current degree of development of the analytical instrumentation used for final determination in most instance this is not feasible. Concepts like miniaturisation, integration and simplification became key concepts that have already been proved to effectively contribute to solve some of the drawbacks of conventional sample preparation methods and that, in some studies involving size-limited samples, can probably be considered the best, if not the only, analytical alternatives. The present review article focuses on sample preparation, with examples primarily related to liquid and solid matrices, and more specifically on selected modern techniques, i.e. those introduced in the last two decades or so. Most recent developments and achievements in the field will be discussed on the basis of representative examples. Attention will focus in the analysis of trace organic compounds due to the difficulty associated to this type of determination. Nevertheless, if relevant, examples will also be taken from other application areas as far as they involved a chromatographic (or closely related separation) step for the final instrumental determination of the target compounds. –Omic sciences remain out o