Miniaturized, wireless instrumentation is now a reality and this paper describes development of such a system to monitor crack response. Measurement of micro-inch crack width changes in residential structures can now be employed to supplement control of construction vibrations through comparison of environmental (long-term) and blast-induced (dynamic) response. A low power consumption potentiometer displacement transducer and a short communication duty cycle allow this system to operate wirelessly up to a year with AA size batteries. The system described won third place honors in the 2005 Crossbow Smart Dust Challenge, which represented the best executable ideas for wireless sensor networks. Copyright ASCE 2006.