The ever-growing service delivery in electronic government (e-government) in conjunction with the wide immersion of Information and Communication Technologies (ICT) in public sector has underlined the need for reconsideration of the security measures that ensure the inner transactions. Electronic voting represents one of the most common examples of e-government application. The challenge that imposes the ability of citizens to exercise their voting rights in terms of security is imperative. Thus, security experts need to ensure the e-voting processes so as to provide a secure service to citizens. The main principles that must be reflected to the security policies of the system are also identified in the conventional voting systems. The current thesis has used those principles, as well as others imposed by the nature of the system, to model and develop an e-voting system. The functional requirements were the basis of the designed system and of its security policy. The development of the e-voting system was performed by utilizing theWSO2 Identity Server platform, while the security policies were implemented in the XACML language.