Glastir yw cynllun blaenllaw Llywodraeth Cymru ar gyfer rheoli tir mewn modd cynaliadwy. Mae wedi derbyn cyllid drwy Gymunedau Gwledig Llywodraeth Cymru – Rhaglen Datblygu Gwledig 2014–2020, sy’n cael ei hariannu gan Gronfa Amaethyddol Ewrop ar gyfer Datblygu Gwledig a Llywodraeth Cymru. Mae'n talu am ddarparu nwyddau a gwasanaethau amgylcheddol penodol sydd â'r nod o wneud y canlynol:
Glastir is the Welsh Government’s flagship sustainable land management scheme,  and has received funding through the Welsh Government Rural Communities - Rural Development Programme 2014-2020, which is funded by the European Agricultural Fund for Rural Development and the Welsh Government. It pays for the delivery of specific environmental goods and services aimed at: