This paper situates the Henderson Poverty Inquiry in the context of other social security reviews occurring at the time and subsequently. Insights are drawn on the influence of these inquiries by exploring their characteristics, activities and findings and by reflecting on ensuing policy change. The analysis suggests that inquiries make diverse policy contributions across at least three dimensions: nature (inquiries contribute in different ways); extent (inquiries make different degrees of contribution); and temporality (some contribute in the short term; others exhibit a slow burn over many decades). With respect to the Henderson Poverty Inquiry, its contribution included influencing immediate policy change as well as providing an evidence base and strategic approach of value to subsequent policy development and inquiry activity. Its contribution was significant and enduring. This paper concludes by reflecting that wide-ranging social security inquiries have been very rare. Arguably, the last inquiry with breadth was the Henderson Poverty Inquiry. When considered in light of the extensive piecemeal reform of the social security system that has occurred over recent decades, this suggests a comprehensive and integrated review of social security policy in Australia is long overdue.