The Strategic Information Systems Planning (SISP) process is critical for ensuring the effectiveness of the contribution of Information Technology (IT)/Information Systems (IS) to the organisation. A sophisticated SISP process can greatly increase the chances of positive planning outcomes. While effective IS capabilities are seen as crucial to an organisation’s ability to generate IT-enabled competitive advantages, there exists a gap in the understanding of the IS competencies which contribute to the forming of an effective SISP capability. In light of these gaps, this study investigates how do IS competencies impact the SISP process, and its outcomes? To address this question, a model for investigating the impact of IS collaboration and IS personnel competencies on the SISP process is proposed. Further research is planned to undertake a survey of top Australian organisations in industries characterised by high IT innovation and competition, to test the proposed model and hypotheses.