Gerhard Schleenstein is one of the odour experts working on D-NOSES. He is a senior environmental consultant, with 18 years of working experience. He graduated from the Technical University of Berlin as an Environmental Engineer and holds a MSc from Lüneburg University. In 2009, Gerhard founded Ecotec, an environmental consultancy which specializes in solid and liquid waste and odour management, based in Chile. Ecotec has notably been commissioned by the Chilean Environmental Ministry to draft a roadmap for the comprehensive regulation of odours in the country. Today, he brings us some insights about odours.