With the launch of their inequality campaign this week, Oxfam have deepened the groundswell of opinion that includes billionaires, the IMF, World Bank, and millions of ordinary people. Their campaign report – “Even it up” – is a welcome addition to discussions around inequality.

In Africa, inequality slows poverty reduction. Despite Africa’s impressive growth, a business-as-usual trajectory means that Africa will account for 80 percent of the world’s poor by 2030. Inequality keeps millions in poverty. It also undermines growth and contributes to economic instability.

In this year’s Africa Progress Report – Grain, Fish, Money – we argued that growth in the agricultural sector could directly benefit the two thirds of Africans who depend on farming for their livelihoods. We urged African governments to boost agriculture in order to generate better, fairer growth for millions.

Oxfam’s report contains many useful recommendations on themes that we also support.

First, equity must be a core principle within the post-2015 development goals. Equity was a core part of the Millennium Development Goals (MDGs), but not explicitly so. And some countries progressed towards the 2015 MDGs despite growing inequalities.

Equity is critical to poverty reduction. We have already picked the low-hanging fruit on poverty reduction. Sustained progress in child and maternal health, for example, requires strategies to tackle malnutrition, extend basic health services to remote areas, and empower people to hold service providers to account.

An obvious starting point for post-2015 strategies therefore will be the identification of who is being left behind. The Overseas Development Institute and others recommend the use of rolling equity targets – three to five year “stepping stones” – that focus on narrowing disparities. These “stepping stones”, determined nationally, could focus on disparities across wealth levels, gender, and regions, for access to basic services such as health and education.

Second, fiscal policy can be used more effectively to protect the more vulnerable segments of society. Tax avoidance and evasion are global problems but hit Africa hardest, especially in the extractives sectors, effectively depriving people of health and education. The global community should give better representation to Africa in discussions on tax reform. In the meantime, Africa needs technical and financial support to build capacity for tax administration in order that it can also benefit from new OECD standards on tax.

African governments must reform their fiscal policies to benefit society’s poorest groups. Move away from taxes – such as value added tax – that disproportionately hit the poor. Move away from subsidies – such as fuel subsidies – which benefit the wealthiest most. Africa spends three times as much on energy subsidies than on social protection.

The stakes are high. As the Oxfam report rightly says, some inequality is necessary to reward talent, skills, and a willingness to innovate and take entrepreneurial risk. But today’s extreme inequalities block too many people from achieving their true potential. That is a loss – not just for the individuals, but for society too.