On June 22 this year, Sotheby's London will offer for sale one of the most important oils by celebrated Austrian artist Egon Schiele ever to come to the market.

The painting - Häuser mit bunter Wäsche, 'Vorstadt' II of 1914 - ranks among just a small number of significant cityscapes by Schiele remaining in private hands. It should make an excellent investment.

Having been acquired - in the year it was painted - by Schiele's friend and greatest patron Heinrich Böhler, the painting was subsequently sold by Böhler's widow in 1952 to Rudolf Leopold, founder of the Leopold Museum in Vienna, which boasts a pre-eminent collection of Austrian 20^th century art. The work now comes to the market for the first time, with an estimate of £22-30m/$36-50m.

Helena Newman, Chairman, Impressionist & Modern Art, Sotheby's Europe, said:

"We are thrilled to be offering this masterpiece of 20^th century art in our June sale. Its richness of colouration achieves a transcendental intensity that epitomises Schiele's unique contribution to the development of 20th-century art.

"The painting is unquestionably one of the greatest Schiele oils ever to come to the market but, quite aside from its rarity and quality, it is also distinguished by an illustrious provenance, having never before appeared on the auction market, and having previously resided in just two great collections since the artist painted it - those of Heinrich Böhler and the Leopold Collection."

Peter Weinhäupl, Managing Director of the Leopold Museum, said: "The Leopold Museum today is committed to affirming its position as the pre-eminent repository of Austrian Modern Art and the decision it has taken with this sale is a testament to this commitment.

Schiele's painting 'Houses with Colourful Laundry'

"While this painting will be missed, the museum is fortunate to hold eight further Schiele cityscapes of superb quality in its collection."

Painted in 1914, at the height of Schiele's short career (he died in 1918 at the age of just 28) Häuser mit bunter Wäsche, "Vorstadt" II - translated as Houses with Colourful Laundry, "Suburb" II - is one of Schiele's most impressive cityscapes.

The painting, an oil on canvas, is loosely based on motifs drawn from Krumau. It was this town in Southern Bohemia in which Schiele's mother was born, and to which Schiele and his lover Walburga (Wally) Neuzil moved in 1911, in order to escape what they perceived as the claustrophobic atmosphere of Vienna (ironically, they were soon driven out of the town by the residents, who strongly disapproved of their liberal lifestyle, and returned to the environs of Vienna a year later).

The houses in the painting are rendered as if stacked up one upon the other, rising into the picture-plane with their vibrant roofs and walls. This compositional format, using the elevated perspective, is typical of Schiele's most accomplished cityscapes.

It suggests the vantage point of a soaring bird, or a visionary, hovering above the landscape and looking down from the heights. Commenting on the painting, Professor Dr Rudolf Leopold, founder of the Leopold Museum, said:

"The colorful laundry, infused with much more motion than its surroundings, may in Schiele's eyes have symbolized the still innocent and carefree lives of children and young people. Grown old, they remain in their dwellings, crowded into a constricted space.

"This idea is suggested by the interlocking character of the houses, and is underscored by the physiognomic suggestion of the two house walls on the right with their 'window eyes'. Just behind the houses begins an open, empty no-man's land. The mountain peaks emerging from the clouds - perhaps meant symbolically as the goal of human longing - appear inaccessible."