Abstract: A bidirectional code decoding method and apparatus is presented. It uses a class of Reed-Solomon codes capable of bidirectional decoding, more specifically, those for which a value of L for a Galois Field element &agr;L is chosen as −(R−1)/2 for odd values of R and 2(m−1)−R/2 for even values of R. When the symbols of such codes are received at a decoder in a reverse order (from that in which the symbols are normally received) during a reverse directional read, the decoder produces reverse directional syndromes S˜(−k) and converts the reverse directional syndromes S˜(−k) to syndromes S(k) by multiplying S˜(−k) by &agr;(n−1)k for k=L, L+1, . . . , L+R−1.