What is described herein are conditioning/styling tetrapolymers of vinyl caprolactam (VCL), vinylpyrrolidone (VP), dimethylaminopropyl methacrylamide (DMAPMA) and C8-C24 alkyl quaternized dimethylaminopropyl (meth)acrylamide or methacrylic acid quaternized monomers (QDMAPMA), in a defined compositional range. Hair and skin care compositions which include these tetrapolymers exhibit advantageous low tackiness and high humidity resistance.