Dr Morrissey worked to develop the New Zealand Treasury's 'Living Standards Framework' that has been used as the basis for 'Wellbeing Budgets' since 2019.  She spent a number of years at The Treasury, managing the tax policy team, and as Principal Advisor in the Office of the Chief Economist.  She has worked as a public servant for almost ten years and is currently the Director of Policy and Research at the Retirement Commission in New Zealand.  She is also a Research Associate at the Public Policy Institute at the University of Auckland.

Dr Morrissey is also one of the co-founders of the Wellbeing Economy Alliance (WEAll) Aotearoa (New Zealand) Hub.  The Hub facilitates collaboration and activity towards building a wellbeing economy, and links into the global WEAll movement.

Dr Morrissey has previously spoken on wellbeing at a number of international events, including the OECD Forum in Paris, and the 6th OECD World Forum on Wellbeing in Korea.

Dr Morrissey is a Chartered Accountant by profession and was made a Fellow (FCA) in 2018.  Her PhD is in Taxation and examines policy and gender.