Local government organizations such as municipalities often seem unable to fully adopt or implement web accessibility standards even if they are actively pursuing it. Based on existing adoption models, this study identifies factors in five categories that influence the adoption and implementation of accessibility standards for local government websites. Awareness of these factors is important for stakeholders adopting and implementing web accessibility standards. To further develop and understand these factors, this study has identified and interviewed experts in the field of (organizational) accessibility. This has led to an extension of the existing models. The extended model was then validated by interviews with key stakeholders. The outcome of this study places existing adoption models in a new context. The result is an adoption model that contributes better to explaining adoption and implementation processes within eGovernment systems and organizations. This adoption model aims to better help local governments in the identification of factors influencing the actual adoption and implementation of web accessibility standards in their situation. The model explains how factors in the different categories contribute to the adoption and implementation of web accessibility standards. The model may also be applicable to the adoption and implementation of other guidelines and (open) standards within local government.