As one of six Centers in the US Food and Drug Administration, the Center for Food Safety and Applied Nutrition, CFSAN, is a regulatory agency tasked with protecting American consumers from food hazards. Case studies from food born outbreaks including diverse products such as hamburger, infant formula and flour, as well as produce including spinach, peppers and tomatoes will be discussed to illustrate the biological and food matrix considerations for engineering useful sensors. Fundamental scientific and engineering principals such as signal to noise ratios and limits of detection are balanced by economics for new technologies and will be discussed in the context of food borne pathogens including Escherichia coli, Salmonella and Cronobacter.