From 1889 to 1914 he served as the Diocesan Architect of Vitoria, and thus was involved in the construction and restoration of numerous religious buildings in the province of Álava.
[2] He also held various municipal positions and had an important role in the founding of the Escuela de Artes y Oficios in 1891.
His Chapel of the Sagrada Familia of 1905 is one of the most important examples of eclectic architecture in the Basque Country, at around the same time he also designed the new Bridgettine convent in Vitoria.
[5] During the late 19th century he also built and reformed numerous residential and service buildings, including the Palace of Montehermoso [es].
[6] Starting in the early 20th century Íñiguez de Betolaza abandoned eclecticism and adopted a style influenced by Viennese Modernism and Art Nouveau.