E-Appointment services could be considered as simple solutions providing significant benefits for improving the accessibility and efficiency for delivering public services requiring face-to-face interactions. Given the high number of services requiring appointment scheduling across government, a government-wide approach which provides e-appointment service as part of a software infrastructure for e-Government is clearly appealing over agency-specific solutions. The paper presents a case study of a one-stop e-Appointment service proposed as part of software infrastructure for e-Government. Relying on appointment-related information maintained by individual agencies, the service enables applicants to seamlessly arrange appointments to visit government agencies or centers providing public services through the one-stop government portal. We define a generic business process underpinning the delivery of one-stop e-Appointment service, propose an approach for implementing each of the business process steps, and present a concrete software solution to support the process. In addition, the paper discusses how the proposed solution addresses some of the challenges identified for delivering the service as part of software infrastructure for e-Government.