In 1923 she moved back to Vienna and opened her own studio together with Anny Moller-Wottitz. During these years she commuted between Vienna and Germany. In 1925 she decided to stay in Vienna. Franz Singer followed her, and in the same year the Atelier Singer-Dicker was established in Wasserburggasse in the 9th district, designing furniture and apartments as well as architectural plans. The two complemented each other ideally as a team. Friedl Dicker enlivened Franz Singer’s constructions, she experimented with materials, colours, and textures. The Ateliergemeinschaft created residential furnishings and buildings of outstanding modern design in Vienna. Their designs were soon in great demand in Vienna.

The conception and design of the small apartment and one-room apartment, which combined several functional areas within one room, was a new field of activity for architects in the twenties. In the social sphere, these housing designs emerged due to limited spatial capacities. In the bourgeois milieu, the small apartment or the one-room apartment had a different intention. Here it was rather a fashionable phenomenon to have an apartment designed with simple, functional furniture in a small space, as the Atelier Singer-Dicker designed it.

In 1930, the Atelier Singer-Dicker was commissioned to furnish the Montessori kindergarten in the Goethe-Hof. The two ideally implemented the ideas of promoting individuality and creativity. However, the model kindergarten of Red Vienna was partially destroyed as early as 1934 during the February Uprising. The National Socialists had the kindergarten dissolved and closed in 1938. The other buildings of the studio in Vienna were also destroyed and demolished.

In 1931 Friedl Dicker received an invitation from the City of Vienna to hold classes for kindergarten teachers and she also gave art lessons to children. This marked the beginning of a new phase in her life; she left the working group with Franz Singer and moved into her own studio. She joined the communist party and increasingly reflected social events with her artistic work, creating anti-capitalist posters and collages. After an arrest and humiliating interrogation, she fled to Prague. Here she had relatives and met Pavel Brandeis, whom she married in 1936.

She painted, taught children, and worked with the Vienna studio on home furnishings. Due to the increasingly critical situation, friends tried to convince Friedl to leave Europe. Anny Moller-Wotitz was in Palestine with her husband at the time and sent her a visa. But Friedl turned it down; she wanted to stay with Pavel. The couple moved to Hronov, north of Prague, in 1938. Both worked in a textile factory. Friedl drew and painted. Living conditions became increasingly difficult. They had to move into smaller and smaller accommodations, finally into one room. In late autumn 1942 they were deported to Theresienstadt. Friedl Dicker-Brandeis had herself assigned to the children’s home L410, where she gave painting lessons to children. She wanted to work with the children and gave them her energy – and the children were the source of her strength. Painting helped the children to survive the terrible everyday life. Friedl also helped to make the rooms and camps more comfortable with the simplest means. She created costumes and stage design for a children’s play.

Before she was deported, she packed many of the children’s drawings into a suitcase that was hidden in an attic. On 6 October 1944 Friedl and Pavel were transported to Auschwitz. Friedl was gassed to death.

The children’s drawings were rediscovered after the end of the war and brought to the Jewish community in Prague. Already after the first exhibition it was said: “The children’s works are brilliants in the crown of world culture”. Edith Kramer, a student of Friedl Dicker said: “In the drawings of the children of Theresienstadt and in her own work Friedl Dicker-Brandeis lives on. … There are many forms of survival.”