Edition (re-issued in 2021). In 2016 Heritage Records released a box set of the complete Grainger music for two pianos four hands, featuring the three earlier recordings by Thwaites and Lavender together with a fourth CD recorded in 2016 by Penelope with Timothy Young. BBC Music Magazine (February 2017) commented "passion undimmed, along with dexterity, the playing’s flair and precision are unchanged...Listening again only makes the heart grow fonder...I can't think of another composer who so quickly and quirkily enhances life." Other activities Her lectures and broadcasts on the composer and detailed research into his life and work led to her editing The New Percy Grainger Companion (Boydell & Brewer 2010, paperback edition 2016). She was Artistic Director for two major Grainger Festivals in London (St John's Smith Square in 1998 and a four-day celebration at King's Place in 2011 to commemorate the 50th anniversary of Grainger's death. Her interest in promoting Australian composition led to her founding and chairing the international Performing Australian Music Competition which took place in London in 2001 and 2008, attracting young musicians from 20 countries who chose and performed music of 80 Australian composers. The competition still awaits a long-term sponsor. From 2013 to 2019, she served as Chairman of the Order of Australia Association UK/Europe. Composing work In the same year that she gave her second Wigmore Hall recital (1976), her musical (with Alan Thornhill) Ride! Ride! (based on an incident in the life of John Wesley) premiered at the Westminster Theatre in London's West End, following a nationwide tour. The musical has had more than 40 productions since then – both amateur and professional - and a concert version was recorded in 1999 on the SOMM label, starring the legendary actor, Keith Michell. Thwaites's compositions include songs, organ and piano works, chamber music, film and ballet music. She is published by Bardic Edition, whose catalogue is now distributed under the Schott Music imprint. In 2020, SOMM recordings released "From Five Continents", a CD of twenty-four of Penelope's choral works and songs, with Ex Cathedra under Jeffrey Skidmore and soloists Carolyn Sampson, James Gilchrist and William Dazeley. The CD has been featured on the BBC, ABC, Classic FM, Scala Radio, and on YouTube. Recognition Penelope received the International Grainger Society's Medallion in 1992 and was appointed a Member of the Order of Australia (AM) in 2001 "for service to music through the performance