FIR filters are one of the most important areas of study and implementation in DSP. As such, this paper is aimed at engineers who already know the basic operation and properties of FIR filters, but want to go further and understand specific FIR filter algorithms and their implementation in modern DSP systems. This paper, starting where the “FIR Fundamentals” papers end, covers practical applications of FIR filters used as matched, comb, half-band, minimum phase, and interpolation/decimation filters. Several popular schemes for improving the functional efficiency and hardware complexity of FIR filters will be described. Practical aspects of converting low-pass FIR filters to bandpass filters will be discussed, along with the notion of complex FIR filters.