Cyfieithiadau i’r Gymraeg, 1958-1988, gan Trefor Williams (bu f. 1988), ysgolfeistr ym Mhorthmadog a Llandudno, o nifer o ddramâu Saesneg. Fe’i cyflwynwyd tros nifer o flynyddoedd mewn cystadlaethau cyfieithu yn yr Eisteddfod Genedlaethol o dan amrywiaeth o ffugenwau megis 'Tudur', 'Madog', a mwy. Ymhlith y casgliad mae copïau Saesneg o ddramâu ochr yn ochr â’u cyfieithiadau Cymraeg, e.e. 'Educating Rita' (Willy Russell 1947-) a 'Death of a Salesman' (Arthur Miller 1915-2005).
Yn wreiddiol o Drefor, sir Gaernarfon, bu Trefor Williams, ynghyd â J.T. Jones, yn gyfrifol am sefydlu Clwb y Garreg Wen, Porthmadog.

Cyfres o lythyrau a chardiau cyfarch oddi wrth J. T. Jones, wedi eu cyfeirio at Trefor Williams a’i deulu, ac at Owen Parry, ynghyd â deunydd coffadwriaethol am J. T. Jones a gasglwyd gan deulu’r rhoddwr; Chwefror 2025.

Scripts formerly held as stock at DAW as loan from theatre companies across Wales, with titles beginning with 'D'. Titles included are as follows:

'Y Da, Y Drwg, a'r Di-Gem', no author, no date.
'Dan Y Sycamorwydden', Welsh adaptation by Bob Roberts of 'Under The Sycamore Tree' by Samuel Spewack, no date.
'David' by Dic Edwards, no date.
'Ddoe A Heddiw', performed by Merched y Wawr Rhanbarth Glyn Maelor at Eisteddfod Genedlaethol Cymru Sir Dinbych, 2001.
'Ddoe Yn Ôl', no author, no date.
'Ddoe Yn Ol', Emyr Edwards, 2004.
'Y Ddraenen Fach' by Gwenlyn Parry, [1961].
'Deadline', by Andy Andrews for Gwent Theatre, 1992.
'Deathwrite', by Labi Siffre, no date.
'Dedwydd Briodas', Welsh adaptation of 'When We Were Married' by J. B. Priestley, no date.
'Deg O Ddynion Bach Duon', Welsh adaptation of Agatha Christie's 'And Then There Were None' by [Eirian Evans], no date.
'Denouement (A Play For Europe)', by C.S. Nicholls, no date.
'Diffinia!', directed by Carys Huw for Cwmni'r Frân Wen, 1991.
'Dinas Barhaus + Tair Drama Arall', W. S. Jones, 1968.
'Disgwyl Y Trên', by E. B. Byron Jones, 1959.
'Diwedd Y Byd', Meic Povey, [2001].
'Dim Ond Heno', by Gwion Lynch for Cwmni Theatre Gwynedd, 1991. Winning drama at Eisteddfod Bro Delyn, 1991.
'Doctor Di-glem', no author, no date.
'Doctor Ffawstws', a Welsh adaptation by Bob Roberts of 'Doctor Faustus' by Christopher Marlowe, 1592. Submitted for entry at Eisteddfod Genedlaethol Dyffryn Clwyd, 1973.
'Dod I Ben', by 'Eilun', submitted to Eisteddfod Genedlaethol Maldwyn a'r Gororau, 2003.
'Dr Arlecchino' / The Imaginary Doctor', Welsh and English copies, no author, no date.
'Dracula', adaptation by Anne Pearson for Torch Theatre Company Ltd., of the original by Bram Stoker, 1978.
'Drama'r Ddrama', Welsh adaptation by Garry Nicholas of 'Play On' by Rick Abbot, no date.
'Dringo Yr Andes', winner at Eisteddfod Genedlaethol Casnewydd 2004. No author, no date.
'Drws Priodas' by Gruffudd Parry, no date. Based on two works by William Williams Pantycelyn, 'Drws Y Society Priodas' and 'Cyfarwyddwr Priodas', 1777.
'Duges Amalffi', [Gwyn Parry], no date.
'Y Dyn Llnau Bogs' by 'Ini-Mini-Mô', no date.
'Y Dyn Swllt', no author, no date.
'Dyrchafiad Jonathan', by Patricia Chown, no date.