Many private organisations and public sector agencies develop information and communication technology (ICT) business cases, and utilise them for better ICT investment decision making. The development of ICT business cases in private sector is relatively ad hoc and compact in size. In contrast, agencies in public sector are accountable to taxpayers for their use of public funds and to ensure that public money is spent efficiently and value for money is obtained. This accountability in the public sector has cultivated a norm of increased control over public agencies’ spending and led to the requirement for a robust and evidence-based ICT business cases. So far, scant research has investigated the development and utilisation of ICT business cases in the public sector. To fill this gap, this research-in-progress proposes a study to take a closer look at ICT business case approach in the public sector and its related benefits and disadvantages perceived by ICT business case experts. Preliminary data was collected from archival data and interviews with ICT business case experts working at a professional services firm. Our preliminary findings show that a structured and complex two-pass ICT business case approach was adopted in the Australian Federal Government. This research-in-progress briefly outlines benefits and disadvantages which business case practitioners can adopt to enhance their related ICT business case approach.