The Dino and Ernesta Santarelli Foundation, which stems from the Milarium cultural association established in 1999, was initiated in 2004 by Paola Santarelli and Ernesta Santarelli D'Orazio in memory of Dino Santarelli; the name was extended in 2008 in memory of both parents. It is a non-profit organisation of social utility: it was established with the aim of fostering, supporting and promoting research and the dissemination of art history and the history of Rome in Italy and abroad, with particular reference to stone sculpture, the coloured marbles of imperial Rome and glyptics. In recent years, the Foundation's artistic focus has been extended to stone painting. The Foundation promotes exhibitions, research, seminars and scholarships, and editions of art books. It has also acquired and preserves part of Federico Zeri's sculpture collection and promotes its studies. The initial nucleus of the collection, initiated and carried on by the female branch of the Santarelli family, has been considerably increased in recent decades through targeted acquisitions that have made it possible to build up a numerous collection of sculptural works ranging from the Ptolemaic era to Canova and Thorvaldsen. In addition to sculpture, the collection includes a large collection of around six hundred works of glyptics representing the technical and artistic history of the discipline from the Mesopotamian age to the 19th century. The collection of gems, seals and cameos was exhibited for ten years in the same rooms of the Capitoline Museums where the exhibition The Colours of Antiquity. The Santarelli Marbles at the Capitoline Museums. In the field of sculpture, the Santarelli collection stands out on the international scene for its focus on the coloured marbles imported to Rome in the imperial age. By acquiring entire collections and single pieces on the Italian and foreign antiques markets, the result is a complex of architectural fragments and samples that make it probably the richest and most important private collection worldwide. The collector's choice adopted aims to highlight a fundamental theme in the history of Rome and its artistic stratification.

The interest in Rome and its history has led the Santarelli Foundation to focus on contextualising the art of the past in the present, working on a multidisciplinary level with various Italian and international institutions.
In 2016, a close collaboration began between the Santarelli Foundation and Flat Time House (FTHo), the home-studio of John Latham (1921-2006) recognised as one of Britain's most significant and influential post-war conceptual artists. After being threatened with closure, the future of FTHo has been secured thanks to the Foundation's intervention, allowing the organisation to continue to operate independently in Latham's original home-studio in Peckham.
Since 2018, the Santarelli Foundation has been promoting the independent project Villa Lontana, which is interested in the development of ancient and contemporary artistic practices through the realisation of exhibitions, publications, film series and sound projects.