There are seven antigenically distinct FMDV serotypes; O, A, C, Asia1, SAT1, SAT2 & SAT3, with no cross protection between serotypes. There are five known antigenic sites on the FMDV capsid against which neutralizing antibodies bind to confer protection against the viral infection. VP1 contains the virus attachment motif (RGD) on the G-H loop that binds to the cellular receptor integrin for all the seven serotypes known and carries the serotype specific immune dominant epitope which is part of antigenic site 1. It has been shown that the RGD motif is not an essential constituent of peptides able to elicit neutralising antibody responses against the virus (Brown et al., 1999). Monoclonal antibody (Mab) D9 is a neutralising Mab that binds to the linear immune dominant epitope of G-H loop, where for serotype O, its neutralising activities are affected by the changes at amino acid positions VP1 (L144, L148 and K154). In this study we hypothesised that there are two different types of epitopes on the G-H loop, one is conserved between serotypes, and non-neutralising, while the second epitope is neutralising and serotype specific.