Several structural isomers of vinylsalicylic acid and the corresponding methyl vinylsalicylates have been synthesized in this laboratory previously and have been polymerized and copolymerized with methacrylic acid and with methyl methacrylate. The monomer-ic as well as the polymeric compounds have been tested for their antimicrobial and cytotoxic properties. This article also deals with the sunscreening properties of some polymeric salicylic acid derivatives and their possible use as the effective ultraviolet-absorbing agent in skin protection formulations. The results show that making homopolymers and especially copolymers is a way of increasing one property and decreasing another, making new compounds with more specific properties.