The OECD secretariat has told the Working Party on Private Pensions and the Insurance and Private Pensions Committee (IPPC) that countries overhauling their pensions systems should seek to establish a balance between public and private pensions.   This, it is argued, would help to maintain sustainable pension systems, which would be resilient to economic and other shocks.   The OECD said that long term issues such as the sustainability and adequacy of pension systems should drive decisions on pension systems, rather than short-term fiscal and political pressures.   It called on governments to strengthen their private pension systems and the efficiency and effectiveness of their regulation to help address the challenges of ageing, as reflected in the mandate of the Insurance and Private Pensions Committee, the parent body of the Working Party on Private Pensions.   The secretariat called for better disclosure, communication and pension education on the grounds that the success of a pension system is dependent on the public and policymakers understanding it.   Adequate disclosure and pension education were needed to help members manage their future retirement goals, it said.