Prof. Dr. Wiesław Oleszek is a full professor at the Institute of Soil Science and Plant Cultivation, State Research Institute, Pulawy, Poland. In 1975, he started his research activity at the Institute of Soil Science and Plant Cultivation, Pulawy, as a researcher. In 1979–1980 and 1987 (one year each), he was a visiting fellow at Cornell University USA, performing research on glycoalkaloids in tomato and its progenies In 1989, he was a visiting scientist at the Food Research Institute, Norwich, U.K., working on the membrane activity of alfalfa saponins and NMR techniques for their structure elucidation. In 1992, he spent time at INRA, Avignon, France, in a Postdoctoral Trainee internship, working on pear phenolics. In 1992 (till 2010), he assumed the position of the Head of the Biochemistry and Crop Quality Department, and from 2010 to 2024, he had the position of Director at the Institute of Soil Science and Plant Cultivation, Pulawy, Poland. His research interest includes isolation, purification, structural and quantitative determination of plant natural products, natural toxicants of plants-allelopathy, natural pesticides, post-harvest quality of agricultural products, natural antioxidants, and anticarcinogens, nutraceuticals, biosynthesis of secondary metabolites, food and feedstuff additives, functional food, agronomy, production systems, climate change about agriculture, and bioeconomy.