A method of providing papilloma virus like particles which may be used for diagnostic purposes or for incorporation in a vaccine for use in related to infections caused by papilloma virus. The method includes an initial step of constructing one or more recombinant DNA molecules which each encode papilloma virus L1 protein or a combination of papilloma virus L1 protein and papilloma virus L2 protein followed by a further step of transfecting a suitable host cell with one or more of the recombinant DNA molecules so that virus like particles (VLPs) are produced within the cell after expression of the L1 or the combination of L1 and L2 proteins. The VLPs are also claimed per se as well as vaccines incorporating the VLPs.