Abstract Counterfeit parts are marketed with the intent to deceive the customer. This intent to deceive defines a counterfeit part and separates it from faulty parts, which have defects that are unknown to the manufacturer or distributor. This paper presents three cases in which counterfeit electronic parts were assembled into hardware items and later found to be faulty in some manner. Laboratory techniques used to identify these parts as counterfeits are presented. Non-laboratory techniques that could have prevented the parts from entering service in these cases are also described. Techniques to combat counterfeit parts range from very simple observation of the parts and the paperwork to failure analysis carried out in a laboratory environment. In all of these cases, the potential existed to detect the counterfeit parts prior to assembly into hardware and prior to field deployment of the defective devices.