Publishing a book that tackles the sharing of news content through social media channels is brave. As most media researchers acknowledge, change in the media industry is not so much constant as there is a constant iteration of compositions of relations that may exist for weeks or years and then are displaced again with yet other relations and practices. Yet, running through these emergent practices and complicating it further are remediated media forms and consumer habits developed in earlier eras. Sharing News Online: Commendary Cultures and Social Media News Ecologies by Fiona Martin and Tim Dwyer, and individual chapters co-authored with an assortment of their research partners, valiantly grapples with the series of challenges this presents. Their stated goal is to better understand the how and why of what we share as a part of everyday media practices. Across the ten chapters, they stake out some of the key challenges for media researchers and professionals alike, with some key contributions relevant for journalism studies.