Artist in stained glass; Born October 25, 1914; Died February 7, 2007. With the death at 92 of Sadie McLellan, Scotland has lost not only one of its finest artists but a unique, engaging personality. In a career spanning some 60 years, Sadie's work as an artist in stained glass stood out from the pack not only due to its clarity of conception but, in a country where so many careers in the arts are undermined by sycophancy and pettiness, because of its fearless and trenchant independence of thought and action.

These were the characteristics that so endeared McLellan to the poet Hugh MacDiarmid, who recognised in her a kindred spirit who would never pander to popular taste or sentiment in pursuit of her artistic vision. His poem The Terrible Crystal was dedicated to her in profound admiration.

McLellan was small in stature, with a bird-like combination of strength and elegance and many a Scottish macho man found himself short of a few inches after a brush with this stormy petrel. A diva, in the best sense of that word, Sadie was always deeply critical of her own work and that of her contemporaries.

Born in Milngavie, in 1914, her career - like that of her brother, Robert, the playwright - began under the influence of her father, an idealistic socialist whose return from the Great War was so movingly recalled in The Herald's poetry column on January 20.

Her teacher at Bearsden Academy, the artist Willie Armour, persuaded her to go to the Glasgow School of Art, where, in 1933, in her third year, she entered the stained-glass workshop of Charles Baillie, designer of the famous Rogano restaurant, in Glasgow, and a prolific artist in stained glass.

McLellan was impressed by the possibilities and challenge of the medium. She was already a confident artist and her diploma design - a depiction of Mary Queen of Scots - though influenced by Baillie, showed remarkable assurance. She was awarded the John Keppie travelling scholarship, which she used to visit Scandinavia. Her academic year was spent at the Danish Royal Academy of Art, in Copenhagen, under Professor Einar Utzon-Frank, a noted sculptor. While in Copenhagen McLellan produced designs for windows, including a three-light window for a crematorium and a speculative design for the great west window of Glasgow Cathedral. She also executed her first domestic commission, for four panels illustrating the signs of the zodiac, for a house in Fredensborg. When her completed cartoons were exhibited at the school of art, they were greeted with enthusiastic approval.

In 1938 she contributed a mural, a stained-glass panel and an embossed panel to the Women's Pavilion at the Empire Exhibition. The stained glass was purchased by Lady Maufe, the artistic director of Heal's of London. With the proceeds, McLellan funded a tour of Germany, Italy, Switzerland and France, visiting Paris and Chartres.

For a time, she joined the staff of Glasgow School of Art and, as a contemporary noted, "the school changed when she arrived, she brought her creative energy with her like an aura".

In 1940, she met and married Walter Pritchard, of Dundee, a stained-glass artist and muralist who taught on the staff of Edinburgh College of Art. Walter subsequently joined the staff of Glasgow School of Art.

As a colourist, Sadie was a sublime and potent influence on all who came into contact with her work. Her two windows in Glasgow Cathedral show her early style at its best. In 1953, she was awarded a significant commission to execute a scheme of 10 windows for the Robin Chapel of the Thistle Foundation in Craigmillar, Edinburgh. Eight depict incidents from Bunyan's Pilgrim's Progress and are some of the most vigorous and imaginative images in twentieth-century Scottish art.

In 1958, a visit to France and its revolutionary glass schemes, just completed at Ronchamp by Corbusier and at Audincourt by Leger, took McLellan in a new and exciting direction. Determined that Scotland should share the revolution, she began a period of intense experimentation that resulted in the creation of at least six exceptional panels. Only two remain in Scotland: a moving and exquisitely coloured Pieta (now in the National Museum of Scotland), and a rich and sensuous panel, The Lovers (now in a private collection). Five windows in Cardonald Parish Church and a scheme for St Cadoc's Church, in Cambuslang, are among the highlights of this second period.

It was McLellan's courageous pioneering of a new form of architectural stained glass and concrete known as dalles de verre, however, that propelled her in to the forefront of Scottish architectural design. In 1959 she made her first experimental window in this new medium, and, in 1960, completed her first installation, at Alloa Parish Church.

In 1964 she followed this with an extraordinary window for the restoration of the medieval Abbey of Pluscarden, near Elgin. Its chief feature was a huge oculus depicting the Woman of Revelation and the red Dragon.

Nothing this big in stained glass had been attempted in Scotland and when McLellan exhibited half at an Arts Council exhibition, the contrast between the diminutive artist and the scale of the glass was as arresting as its powerful design.

McLellan never rested on her laurels and had begun developing ideas for a Ronchamp-style scheme in dalles de verre in which the glass and its subject, Christ's Passion and Crucifixion, would assume a central role in the design of the building. Her efforts bore fruit in 1965 when she collaborated with the rising stars of Scottish architecture, Isi Metzstein and Andy MacMillan, in the creation of the Church of the Sacred Heart in Cumbernauld. In this and subsequent designs, McLellan's work marked the high water mark of twentieth-century Scottish stained glass. In 1990 she retired to Nova Scotia, where her daughter, Judith, is an architect.

In 1996, Glasgow School of Art recognised McLellan's contribution by awarding her a Fellowship. Her friends and former students will lament the passing of a truly inspirational Scot.