Acquiring and processing SHM sensor data is a multistep process. Correctly implementing steps at both the detail and systemic level is crucial to the success of the overall SHM effort. Figure 4.1 shows a typical and relatively simple data processing sequence. Multichannel and heterogeneous multisensor data generally involve more complicated sequences and architectures [1]. Real-time monitoring systems require performing data processing steps rapidly and in an automated fashion that removes most of the detail-level operations from the end user [2-5]. This chapter discusses some of the initial and intermediate steps in the overall process, including analog signal conditioning, multiplexing, ADC, data logging, and data transmission networks.