The overall goal of the project Istro-Romanian and Istro-Romanians. Legacy and Heritage is to give a descriptive account of Istro-Romanian (IR), a severely endangered Eastern Romance variety, as spoken today in Croatia and in diaspora, and the people who speak this variety, focusing on the following dimensions: linguistics, sociolinguistics, psycholinguistics, language contact, and multiculturalism. Building on the data collected by the project leader in the fieldwork session of June-July 2016 in the villages of Žejane and Šušnjevica (Croatia), where currently there are less than one hundred active speakers of Istro-Romanian left, and from the latest data, collected by the project leader in the first half of 2018 from the Istro-Romanian (heritage) speakers from the United States of America, the main objective of this project is to take a closer look at the Istro-Romanian vocabulary (given language contact with Croatian and American English) and morphosyntax (including clausal structure), bringing together and also emphasising elements of sociolinguistics, psycholinguistics, language contact and life in a multi-cultural and multilingual environment. The choice for “legacy” and “heritage” for the subtitle of our project does not put together two synonymous concepts, rather what we mean by them is two separate things: legacy – from a sociolinguistic and psycholinguistic perspective, namely what Istro-Romanians mean (linguistically) to the communities they live in; and heritage – à la Kelleher 2010, i.e. what the children of ‘native’ Istro-Romanians (of Croatia) that were born abroad or left their country at a very early age speak. Moreover, it is a fact that the Istro-Romanian is slowly dying (if we are to take a look, for instance, at the continuously decreasing number of speakers mentioned, across time, by Weigand 1894, Kovačec 1966, Vrzić 2016, Geană 2017, among others), and parents no longer teach it to their children.