After his death in 1986, Melbourne-based antique dealer, real estate investor and collector William Robert Johnston's treasure trove of more than 1400 18th-century pieces was put on public exhibition.
The collection is housed in his former historic East Melbourne townhouse, Fairhall.
Earlier this year, The Johnston Collection gained accreditation by the Australian Museum and Galleries Association, Victoria - joining 77 other accredited museums, galleries and collecting organisations.
The stunning range of English Georgian and Regency, and Louis XV period furniture, paintings, ceramics and objet d'art is displayed in a constantly changing domestic setting at Fairhall.
The museum is heavily supported by volunteers and offers special exhibitions, study days, lectures and workshops during the year.
Collection director and curator Louis Le Vaillant said the inspiration to undertake the hard work for the long process of accreditation began with Felicity Cook in early 2014.
"She said we need to do it, drove it and kept us going," he said. "Everything is scrutinised ... the process challenged us, but it was always a fantastic two-way conversation.
"It has allowed us to work better, and it's very good to be recognised alongside our peers."
Fairhall was Melbourne's first house museum. After William Johnston died, it was refurbished, the collection sorted and, in line with Johnston's wishes, was opened to the public in 1990.
"He wanted to encourage interest and appreciation of what had been important to him," Mr Le Vaillant said.
"He wanted people to be able to come into the house and see the collection up close without rooms being roped off.
"Most of the collection dates from 1700 to 1830. It's predominantly English, as well as Anglo-Indian furniture and light fittings.
"William Johnston was buying and selling things all the time, and this is a remarkable collection in that one individual left such a legacy of commercial and personal interest."
Tours are offered at 10am, noon and 2pm Monday to Friday, with Thursday evening and Saturday tours once a month.
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