Hilary gained a Distinction for an MMus in Choral Conducting at the Royal Academy of Music with Patrick Russill, where as part of her course she was privileged to work with professional choirs including the BBC Singers and Cardinall's Musick. She also gained a Distinction for her MA in Vocal Studies at the University of York and undertook an Advanced Postgraduate Diploma in singing at Trinity College of Music. Following her studies, she returned to the Royal Academy as the Meaker Fellow 2012-13, the first choral conductor to have been thus honoured.
Hillary is also the founder and director of Blossom Street, a guest conductor with BBC Radio 4's BBC Daily Service Singers, conductor of several office choirs, including the winners of BBC2's Sing While You Work, P&O Choir and Assistant Conductor of Barts Choir. She is also a published and award winning composer.