I think it could be a combination of both grassroots and institutional. For example, my organization, PCCY, has trained early childhood professionals and school staff on the behavioral health system in general, and how best to connect children to it (including information on health insurance). So little by little, and with the efforts of others, as well, we've been able to spread the word more broadly about behavioral health and put resources into people's hands to assist them in their work with families.
The same thing can happen with getting more of the community to be trauma informed. If several organizations commit to some small piece of educating and being a resource, we can really make a big difference. As Joel Fine mentioned, there are organizations that have been and continue to do this kind of work, so perhaps the bigger question is: How can we support that work and what more is needed to advance it?
The institutional level work needs to happen simultaneously-- to leverage more resources, and establish more systemic approaches to trauma-- to piggy back on what Sean Halloran said.