Dennis Williams joined the NSW Police in 1965 with the sole purpose of joining the NSW Police Band. He has played Trumpet/Bugle and French horn from 1965 to 1988 when he took over as Director of Music until Dennis took early retirement in 2001 after the band participated in the Sydney Olympics.
After the police band he went to work at Winston Heights Public School as conductor of their three bands and continues to do so.
Dennis plays and conducts in several bands, some of which are Bankstown Brass, Yagoona Brass, Leichhardt Brass, Penrith Concert Band, The Hills Concert Band, Wollongong Brass.
Dennis has played in several orchestras around Sydney including Penrith, Sutherland, Western Sinfonia, Balmain, Strathfield and music theatre productions at the Sydney Opera House.