One of the lenders to the landmark Armory Show in 1913, she also contributed to other exhibitions concerned with raising public awareness of modern art.

At receptions at the home of her parents, artistically inclined Lillie P. Bliss met actors like Walter Hampden, Ruth Draper and Ethel Barrymore.

In the same year, the Association of American Painters and Sculptors was constituted; among its co-founders were Arthur B. Davies, the artist Walt Kuhn and the critic Walter Pach.

Over the years, Bliss acquired numerous paintings by Kuhn and all three played a significant role in the preparation of the Armory Show in 1913, whose aim was to bring the latest trends in art before the American public.

Other venues, such as the conservative dominated National Academy of Design, at this time refused to support current artistic trends.

[1] Six weeks before the Armory Show, Bliss acquired two landscapes by Pierre-Auguste Renoir and Edgar Degas a painting and a pastel, at the New York branch of the gallery Durand Ruel.

From the exhibition, she bought a large number of works of art, including Silence and Roger and Angelica by Odilon Redon.

Unaffected by negative reviews, Bliss acquired the painting Fruits and Wine and eight watercolors by Cézanne from the exhibition compiled by Félix Fénéon at the Montross Gallery in New York in 1916.

Quinn lent 26, Bliss twelve (including five Cézannes and her Degas painting) and Havemeyer two works (both women were anonymous).

The press complained about Quinn as a secret leader of this issue, criticized the self-appointed citizens committee and described the exhibition as "dangerous".

The painting Quinn Hina Te Fatou (The Moon and the Earth) by Paul Gauguin from his collection was described by the newspaper New York World as typical for the odious Bolshevik work which were on display in the exhibition.

After the death of Arthur B. Davies in October 1928, several exhibitions were held to preserve his memory; Bliss borrowed many works of art for them.

In late May 1929, Abby Aldrich Rockefeller invited Bliss and Mary Quinn Sullivan for lunch in order to discuss the establishment of a museum of modern art.

[2] Although Bliss was weakened by cancer the last months of her life, she participated actively in the formation of the Museum of Modern Art until shortly before her death.

Among the most important works from the Bliss collection in the Museum of Modern Art today are Cézanne's The Bathers and his still-life painting, Portrait of Anna Zborowska by Amedeo Modigliani, Still Life in Green by Pablo Picasso, Hina Te Fatou by Paul Gauguin, Port-en-Bessin, Harbor Entrance by Georges Seurat, Interior with Violin Case by Henri Matisse and Silence and Roger and Angelica by Odilon Redon.

In March 1934, the amount agreed upon was available and the Bliss collection, which included works by Paul Cézanne, Edgar Degas, Andre Derain, Henri Mattisse, Amedeo Mogdigliani, Pablo Picasso, André Dunoyer de Segonzac, among others,[4] was legally transferred to the museum.

For example, Degas's Jockeys on Horseback before Distant Hills was sold in the late 1930s for $18,000, in order to purchase Picasso's Les Demoiselles d'Avignon with the proceeds and an additional $10,000.

In 1951, three more works from the Bliss collection were sold to the Metropolitan Museum: Odilon Redon's Etruscan Vase with Flowers, Paul Cézanne's Portrait of Antoine Dominique Sauveur Aubert and Pablo Picasso's Woman in White.

In turn, the Museum of Modern Art acquired through the Lillie P. Bliss Bequest paintings by Henri Matisse, André Derain, Georges Braque, Amedeo Modigliani, Alexej von Jawlensky, Alberto Giacometti, Balthus, Alexander Archipenko, Juan Gris, Pablo Picasso, Fernand Léger, Theo van Doesburg, Marc Chagall, Piet Mondrian, Lyonel Feininger, Arshile Gorky, as well as sculptures by Umberto Boccioni, Henri Matisse, Henry Moore, Constantin Brâncuși, Joseph Cornell, and numerous other works of art.