This report discusses how steering innovation investment in public sector organisations through a portfolio approach can help governments respond to the multi-faceted challenges they face. Portfolio management is a well-known device in the financial sector, allowing for dynamic decision-making processes involving regular reviews of activity and ensuring a coherent distribution of resources among strategic options. The report illustrates how this approach can be applied by public sector organisations to reap a variety of benefits, including avoiding innovation fragmentation and single-point solutionism; tackling risk aversion and learning at the portfolio level; identifying synergies among projects and activities; building value chains among projects and programmes; and layering activities connected to complex reforms. The report also discusses the type of innovation investments or facets a portfolio can help to steer and what these look like in practice.