|The presentation drawing on research project held by Masaryk University (Czech Republic) focuses on the topic of trust media and on the main theoretical and conceptual challenges linked with this topic and rising from the major changes both of audiences’ practices and media environments. News audiences and media environment are transformed by ongoing processes of fragmentation and diversification. Recipients consume news from professional and alternative media (Tsfati, Ariely 2014; Macek et al. 2018) and recirculate news through online platforms (Tewksbury, Rittenberg 2012). These tendencies undermine information and symbolic authority of professional news media (McQuail 2013). Historically, prevailing measures of trust in media are undertheorized and oversimplified and, at the same time, they face validity issues in the current situation as they do not reflect the fragmented and multivocal character of contemporary media environments (Fischer 2016). Contribution presents results of statistical tests of an innovative quantitative tool for assessment general and particular trust in professional and alternative news media which has been developed for fragmented media environments. This measure drawing on Gidden’s notion of trust (Giddens 1990) acknowledges hybrid nature of social trust and, as such, it is focused on reflexive (based on expectation of professionalism of news media) and also affective (based on need to meet to “my” worldview) trust. The proposed measure was tested in survey on Czech youth population carried in CATCH EyoU project (Horizon 2020). The presentation will focus on preliminary exploratory evidence about function and consistency of this measure as well as on its theoretical grounds and its advantages.