Public participation in Sustainable Development Planning (SDP) of cities represents significant challenges to governments and private organizations responsible for developing infrastructure. In this study, a regional government used a series of electronic discussion papers and questions to enable online forum discussions and exchanges between 196 participants on the major SDP issues related to city development up to 2030. This study used a rigorous and structured QSR NVIVO analysis of 690 online forum postings to determine the participants' major SDP concerns for the city over a 20-year period. The collective results of the investigation show that future integrated transport networks, higher density residential and commercial land use, and sustainable population growth are still the subject of concern and intense debate among forum participants, SDP experts and the government. The research also demonstrates the capacity of green information and technology systems to serve as important mechanisms for SDP participation and consultation.