Objectives: There is accumulating evidence about effectiveness of a number of suicide prevention interventions, and a multilevel systems approach seems promising in reducing suicide risk. This approach requires that components ranging from individual-level to public health interventions are implemented simultaneously in a localised region. This paper presents estimated reductive effects on suicide attempts and deaths that might be expected in Australia if active components of the systems approach were to be implemented. Method: The study estimated population preventable fractions which indicate the extent to which suicide attempts and deaths might be decreased if the each of the proposed interventions was fully implemented. The population preventable fractions were based on the best available evidence available in the literature for the risk ratio for each intervention. Prevalence estimates were assessed for each component of the proposed systems approach: reducing access to suicide means, media guidelines, public health campaigns, gatekeeper programmes, school programmes, general practitioner training, psychotherapy and co-ordinated/assertive aftercare. Results: There was insufficient evidence available for the impact of a number of strategies, including frontline staff gatekeeper training, on either suicide attempts or deaths. Taking prevalence of exposure to the intervention into consideration, the strategies likely to bring about the strongest reduction in suicide attempts were psychosocial treatments and co-ordinated/assertive aftercare. The greatest impact on reductions in suicide deaths was found for psychosocial treatment, general practitioner training, gatekeeper training and reducing access to means of suicide. Conclusion: The evidence regarding the overall efficacy of the systems approach is important in identifying what strategies should be prioritized to achieve the biggest impact. The findings of the population preventable fraction calculations indicate that the systems approach could lead to significant reduction in suicide attempts and suicide deaths in Australia. Potential synergistic effects between strategies included in the approach could further increase the impact of implemented strategies.