Lactone-containing compounds having formula (1) are novel wherein A.sup.1 is a polymerizable functional group having a double bond, R.sup.1 is a monovalent C.sub.1-C.sub.10 hydrocarbon group in which some or all hydrogen atoms are substituted by fluorine atoms, and W is CH.sub.2, O or S. They are useful as monomers to produce polymers for the formulation of radiation-sensitive resist compositions which have high transparency to radiation of up to 500 nm and exhibit good development properties. Radiation-sensitive resist compositions comprising the polymers as base resin exhibit high resolution and prevent dissolution in water and penetration of water when processed by immersion lithography. ##STR00001##