In May Mark was appointed the Welsh Government Cabinet Secretary for Finance and Local Government. Amongst other things he is responsible for:
* Development of a Welsh Treasury function
* Tax policy including local taxes (Business Rates and Council Tax) as well as devolved taxes
* Strategic investment decisions in line with the Wales Infrastructure Investment Plan
* City Deals
* Provision of strategic financial direction and management of the resources of the Welsh Government
He became the Assembly Member for Cardiff West in May 2011. Until May this year he was Minister for Health and Social Services in the Welsh Government, where he was responsible for several important pieces of legislation including changes to organ donation in Wales.