Design director

Born: September 18 1959;

Died: April 9 2015.

Moira Gemmill, who has died aged 55, was a highly successful director of design at the Victoria and Albert museum, where she supervised a revamp of the galleries which led to a tripling of visitor numbers, and was responsible for its £45 million design museum outpost in Dundee, which is due to open in 2017.

Earlier this year, she had been made director of capital programmes for the Royal Collections Trust, where she was to supervise extensive modernisation projects for Windsor Castle and Holyroodhouse.

Her great achievement at the V&A was to transform how the museum presented itself, paying close attention to everything from the layout of the building to the logo - "a beautiful piece of typography that had been relegated to a little nook in the corner".

She worked with the MUMA (McInnes Usher McKnight Architects) to rationalise the display area for the Mediaeval and Renaissance collections, sweeping away a warren of offices and storerooms to create a new space with a glass roof. In all, she was responsible for more than £150 million worth of refurbishment, under the Future Plan programme, working with a series of architectural practices, including Nissen Richards Studio, 6a, and Harrap.

She was born on September 18 1959 into a farming family in Kintyre. Her grandmother and aunt were artistic, and her sister is an artist; Moira Gemmill completed an art and design degree at Glasgow School of Art, concentrating on graphic design and photography, but initially found work hard to come by. She eventually got an "excruciatingly boring" post as an illustrator on a technical magazine dealing with the offshore oil industry, which took her to Aberdeen.

With friends, she then set up a small company publishing a magazine called Citygirl, aimed at working women. When, after an economic downturn, it foundered, she found a billet at Aberdeen Art Gallery as head of programme support. Her duties there were mainly planning and staging exhibitions, something she "absolutely loved" and at which she excelled at once.

In the late 1990s, she was appointed head of design and exhibitions at the Museum of London, having been one of the first appointments Simon Thurley, now chief executive of English Heritage, made on becoming director. Together they made the museum, near the Barbican in the City of London, the venue for a number of temporary exhibitions, and pioneered the development of satellite sites for displaying archaeological finds.

Moira Gemmill was then actively sought out by the V&A, which had been through a sticky period in the 1990s when it had restructured its curatorial departments - to public criticism from some members of staff - experimented with charging an entrance fee, and run a much derided advertising campaign describing it as an "ace café with rather a nice museum attached".

Future Plan, under the new director Mark Jones, was an extremely ambitious set of objectives intended to reverse that decline, and to emphasise the V&A's historic position as a design museum. Moira Gemmill was instrumental in every aspect of its introduction. She and her architects had long discussions about colour - she was keen to emphasise that the mediaeval period was not dark, and believed the setting of the exhibits could be central to that educational purpose.

Under her supervision, the opening up of the V&A's spaces, which had been built piecemeal over a period of around 60 years and were previously a maze of dusty corridors, led to an increase in visitor numbers from 900,000 to 2.9 million. She described the process as like a game of Tetris.

She also organised the V&A's expansion beyond the boundaries of Albertopolis. She set up the Clothworkers' Centre for textiles and fashion in Olympia, an outpost at the site of the 2012 Olympics, and was a prime mover in commissioning the V&A Museum of Design Dundee, the first UK design museum outside London, and the first British building by the Japanese architect Kengo Kuma.

Her last role at the Royal Household, which she took up only at the beginning of the year, was created specifically for her, and she was to have supervised major restoration work at both Windsor Castle and the Palace of Holyroodhouse; in December she told Architects' Journal that the latter would be a big job, as it was "beginning to look decidedly municipal".

An elegant figure with boundless energy, Moira Gemmill was a fellow of the Royal Society of Arts and an honorary fellow of the Royal Institute of British Architects. From 2011, she also served as a judge on the Architectural Review's Women in Architecture awards.

She had a huge network of friends, and kept in touch with colleagues from all her posts. She was enthusiastic about all areas of cultural life, and fond of travel and the cinema. Her friends characterised her as open and direct, and exceptionally generous and kind-hearted.

Moira Gemmill was killed while cycling from her home in Kennington, in south London, to her work at St James's Palace last Thursday, after being struck by a lorry at a roundabout beside Lambeth Bridge. She was unmarried.

ANDREW MCKIE