Business with plagiarism and counterfeiting is booming. Globalization, digitalization, the Internet and gullible bargain hunters are making it possible for counterfeiters to achieve worldwide sales and profits worth billions. The damage caused by the original manufacturers is enormous, as are the dangers for consumers. In particular also innovative medium-size enterprises are concerned. The many product examples from the annual Plagiarius competition as well as the regular exchange with affected companies, in particular SMEs, put us in a position to convey the problem in a practical and very descriptive way. The lecture gives a comprehensive insight into the methods used by counterfeiters and contains recommendations on how to prevent and actively combat product and brand piracy in a mix of legal, organisational and technical measures. Numerous practical examples illustrate the unscrupulousness of imitators and show that all sectors - including medical technology - are now affected.