The applicability of the recursive Walsh-Hadamard transformation to FIR and IIR (finite- and infinite-impulse-response) filtering is investigated. It is shown that using a common structure for recursive transforms recently introduced by G. Peceli (1986), the usual frequency-domain FIR filtering problem can be easily converted into a Walsh sequency-domain filtering problem. It is also shown that a simple modification of this structure results in a possible alternative for IIR filter implementations. >