He joined a group of young people, many with anarchist leanings, that included Juan Puig Ferreter.

He wrote in Spanish for the anarchist periodical La Alarma, and in Catalan for the magazine Germinal, both published in Reus.

Aiguader became involved with the Estat Català founded by Francesc Macià, while retaining his USC membership.

[2] As a leader of the Estat Català a l'interior Aiguader travelled to Brussels several times to meet with Maciá.

[3] In March 1931 Aiguader was a founder and director of the Izquierda Republicana de Cataluña (Republican Left of Catalonia).

[3] The Barcelona city government struggled due to large debts, shortage of resources and lack of management skills.

[3] At the second Esquerra party congress in June 1933, after the end of the dictatorship, Aiguader represented the Federation of Tarragona.

[6] After the disturbances of 6 October 1934[b] he was arrested, as were other members of the government, and imprisoned on the ship Argentina, anchored in the port of Barcelona.

[4] After the occupation of France in June 1940 by the German forces, he lived in concealment in various French cities until he was able to escape to Mexico in 1941.

[1] Jaime's younger brother Artemio Aiguader also became a politician, and during the Civil War was interior cpuncelor of the Generalidad of Catalonia.

[12] Aiguader helped with the creation of the Arnau de Vilanova publishing house, and founded and directed the Monografies mèdiques journal from 1926 to 1937.

This monthly journal covered medical and scientific subjects in technical terms in the Catalan language, including articles by Aiguader.

[2] Although Aiguader often spoke about popularizing medicine, and said he wanted Monografies to reach the general public, the articles and advertisements were clearly addressed to medical professionals.

[13] Aiguader planned a Catalan-language scientific encyclopedia for workers and arts and crafts students, but also for the "educated man".

[14] Unlike authors who romanticized Barcelona's Barrio Chino red light district, Aiguader wrote, "There's nothing but dirt and poverty there.