The miscibility of blends of poly(4-vinylpyridine) (P4VP) with blocky copolymers of vinyl alcohol/vinyl acetate (ACA) of different compositions has been investigated and compared to that of the blends with random ACA copolymers. The miscibility window found in both cases is narrower for the blocky ACA blends, indicating the influence of the comonomer sequence distribution. Fourier transform infra-red spectroscopy shows a lower level of pyridine-hydroxy hydrogen-bonding interactions in the case of blends with blocky ACA copolymers. Cloud point curves have been obtained from optical microscopy measurements for several P4VP/ACA blends. Finally, the binary interaction model including the influence of the copolymer sequence distribution has been applied using Balazs and Cantow-Schulz approximations.