Mae'r cysyniad sy’n sail i’r Fargen Newydd ar gyfer y Gweithlu Addysg yn syml iawn. Gwyddom fod addysg ac arweinyddiaeth ragorol yn cael effaith bwerus ar wella canlyniadau dysgwyr. Rydym hefyd yn cydnabod bod addysgu yn rôl broffesiynol gymhleth ac, fel y dywedodd Dylan William, “Teaching is such a complex craft that one lifetime is not enough to master it”. Ond yn ôl tystiolaeth, gellir gwella arferion addysgu ac arwain yn sylweddol os yw ymarferwyr yn cael cyfle, yn unigol ac ar y cyd, i gwestiynu eu harferion a'u datblygu drwy weithgareddau dysgu proffesiynol sy'n seiliedig ar dystiolaeth.
The concept behind the New Deal for the Education Workforce is very simple. We know that excellent teaching and leadership has an extremely powerful impact on raising learner outcomes. We also recognise that teaching is a complex professional role and, as Dylan William says, ‘Teaching is such a complex craft that one lifetime is not enough to master it’. But the evidence tells us that teaching and leadership practice can be significantly improved if practitioners are given the opportunity to engage, both individually and collectively, in career long reflection upon and development of their practice through evidence based professional learning activities.