Derek passed peacefully at home in Mississauga on August 21, 2025, surrounded by family. Derek is survived by his wife of 64 years, Jean; daughters Dr. Julie Williams and Jacqueline (Lewis) Chilton; grandchildren Jessica and William “Liam” Chilton; sister-in-law Cheryl (Martin) Whittingham-Jones, niece Sally and nephew Stephen.

Derek was born in Birkenhead, England, on July 24, 1938, and grew up amidst the challenges of post-war Britain before charting a path across the Atlantic. He first met the love of his life, Jean, while they attended Prenton Prep elementary school. He attended Birkenhead School before qualifying as a Chartered Accountant in 1959. In February 1960 he emigrated to Canada, arriving at Halifax’s Pier 21, and soon began his career in Toronto at what became Coopers & Lybrand.

In 1961 Derek married Jean, beginning a 64-year partnership filled with laughter, dancing, and adventure. Together they raised their family in Mississauga, where their home backed onto the natural beauty of Rattray Marsh.

Derek built a distinguished career with Coopers & Lybrand (later PwC), becoming a partner in 1970 and advising and providing service to multi-national clients across mining, real estate, and consumer packaged goods. In 1972 he started the first Computer Audit Group in Toronto and subsequently held senior leadership roles as Administrative Partner, Partner-in-Charge of the Mississauga office, and later as Risk Management Partner. Derek was a long-serving member of the audit and business assurance teams and served as Treasurer of the Prospectors and Developers Association of Canada from 1998 to 2001. He retired from PwC in 2001 after more than forty years in the profession, leaving a legacy of innovation, integrity, and leadership.

Known for his sharp intellect, Derek had a rare ability to look beyond the numbers—seeing their implications, asking the right questions, and guiding others with clarity and experience. He brought that same curiosity and precision to his passions outside work. He was active in the Owenwood Residents Association, participated in several investment clubs, and was a devoted tennis player and organizer at both the ORC and MG&CC. He enjoyed a good game of cards and spirited conversations on business, finance, and world affairs. Among friends and family, he was known as the life of the party, hosting many lively Christmas and Thanksgiving gatherings filled with laughter and warmth.

Together with Jean, Derek explored the world — from safaris in Africa to the Galápagos Islands, the Australian coast, the Rocky Mountains, and countless journeys across Europe and North America. He loved the thrill of discovery and always returned with stories delivered with humour and a twinkle in his eye.

Derek’s greatest pride was his family. He celebrated Julie’s medical career in paediatric anaesthesia and appreciated her devoted care for him in his final months. He took joy in Jacqueline’s leadership in business and the loving home she and Lewis built wherever they wandered. Nothing gave him greater pride than watching Jessica and Liam forge their own paths, carrying forward his love of learning, travel, cards, and curiosity.

Derek will be remembered as a man of intelligence, integrity, kindness, and good humour. Always ready for a spirited debate, he loved deeply, lived fully, and left a lasting impression on those who knew him.

Donations in Derek’s memory may be made to the Rattray Marsh Conservation Area or to cancer research. Please share your memories.