Altmann previously led a campaign on behalf of 150,000 workers and their families whose company pensions disappeared when their employers' final salary scheme failed. Having been assured their pensions were safe and protected by law, these workers from companies such as Allied Steel and Wire, Kalamazoo Computer Group, Dexion, British United Shoe Machinery and UEF suddenly faced losing their whole life savings and her work contributed to establishing the Pension Protection Fund and the Financial Assistance Scheme. She has also supported the campaign for people whose pensions were placed in peril by Equitable Life.
In 2009 she campaigned against the sudden, short notice increases in women's state pension age, achieving success in reducing the planned rises, and was instrumental in highlighting the injustices of the annuities market, which culminated in the Government's announcement of the end to quasi-mandatory annuitisation of pensions. Although best known for her pensions work, she is also involved in economic analysis and most recently in highlighting the inadequacies of the social care system. She is also a familiar figure on UK TV and radio, speaks both nationally and internationally on pensions policy, retirement and investment issues and has written for most major newspapers on a range of financial and economic issues, and has twice been the recipient of the Pensions Personality of the Year Award. She is a governor and non-executive director of the London School of Economics. and also an advisor to the International Longevity Centre – UK.She was appointed as Director General of the Saga Group in October 2010 where she stayed until February 2013. In 2011 her work as the "leading commentator on pensions and other matters affecting the lives of the nation's over 50s" was recognised when she was presented with the Public Affairs Achiever of the Year award