Foods of animal origin are some of the most challenging for analytical chemists to investigate effectively, particularly for veterinary drugs. The complexity of the matrix and the number of pharmaceutical analogues demands a sophisticated approach to testing, and the different legislative requirements of various countries requires sample referencing that meets a wide variety of regulatory conditions. Protecting human health from banned substances (such as steroids), inappropriate regulated drugs or foods in which substances have exceeded recommended levels is an important issue. In meeting this challenge, we offer LC-MS and GC-MS technologies that effectively detect a range of veterinary drugs, metabolites and transformation products in foods of animal origin.