Prif ffocws y rhaglen ar hyn o bryd yw datblygu’r trefniadau deddfwriaethol a gweinyddol ar gyfer y trethi datganoledig newydd a phwerau ariannol ehangach, a sicrhau cyfnod pontio llyfn tuag at fis Ebrill 2018. Mae Bwrdd Rhaglen o uwch-swyddogion o’r gwahanol adrannau yn Llywodraeth Cymru yn goruchwylio’r gwaith hwn, sy’n cynnig y sicrwydd y cyngor a’r cyfarwyddyd angenrheidiol. Mae’r Trysorlys yn ymwneud ag ystod o brosiectau ar hyn o brys, gan gynnwys: deddfwriaeth Casglu a Rheoli Trethi; rhoi Awdurdod Cyllid Cymru ar waith; Treth Trafodiadau Tir; Treth Gwarediadau Tirlenwi; datganoli Ardrethi Annomestig yn llawn; ac arferion cyllidebol yn y dyfodol.
The main focus of the Programme activity at this stage is to progress the legislation and administrative arrangements for the new devolved taxes and wider financial powers, and to ensure a smooth transition towards April 2018.  Work in this area is being overseen by a Programme Board of senior officials from the stakeholder departments in the Welsh Government, which provides the necessary assurance, advice and guidance.  The Treasury is currently engaged in a range of projects, including: Tax Collection and Management legislation; Welsh Revenue Authority implementation; Land Transaction Tax; Landfill Disposals Tax; full devolution of Non-Domestic Rates; and future budgetary practices.