While specialized wireless technologies have been used to aid the packaging and deployment of sensor systems for decades-particularly in telemetry systems-support has moved to more generalized wireless sensor network (WSN) systems. Commonplace cell and Wi-Fi backbones provide robust options for data delivery, and these mechanisms are further augmented by simpler, lower cost, and lower power delivery technologies such as Bluetooth, IEEE 802.15.4, ZigBee, and 6LoWPAN. Of late, the smartphone and smart-grid markets have accelerated-related technologies. œis rapid growth, high competition, and innovative solution space should be considered when designing sensing systems that require small size, low power, and distributed solutions with limited or no interconnection wires. Unfortunately, the lexicon of terminology used within the markets overlaps and lacks precision, so this chapter focuses more on concepts as opposed to deŸnitions. And since there are countless possible uses of the technologies, the chapter utilizes examples of the real systems and the lessons learned to provide a framework for making design decisions.