Security and trust have become important considerations in the design of virtually all modern embedded systems. The requirements of secure and trusted design are unique: Secure design emphasizes information leakage (or prevention thereof) and dependable behavior. Even strong cryptographic algorithms are of little use if the underlying processor can be tricked into releasing cryptographic keys. This leads to unique design techniques such as design and implementation of boundaries for logical and physical protection, design of protected storage and secure-computing primitives, runtime measurement and reporting of security properties, and implementation of side-channel-resistant hardware and software. Eventually, the embedded-system designer must cope with security as yet another requirement in addition to existing functional requirements, performance, power, and cost. This special issue presents six articles that address various critical aspects of secure embedded-systems design.