Virtually every communications activity can be tracked and transformed into numbers such as tweets, likes, seconds of video viewed, time spent on a website, newsletters opened as well as the actions resulting from it. Despite all this data, digital metrics seems not to be enough to evaluate content and assess quality. Indeed, the communications professional (corporate, digital, public relations…) struggles to find the right KPI’s to assess the efficacy of their actions and prove their impact. To reduce the activity to numbers decorrelates the data from the complexity of the context and choices(Desrosières, 2013; Porter, 1996), but on the other hand, not quantifying their efforts in an “everything is measurable” era puts them into a risk of lacking visibility (Lemieux, 2008) and of being invisible to their peers, target and the management. This metrics related approach turns out to be increasingly problematic when trying to legitimize their role into an organization. This “if it’s not measured it doesn’t exist” philosophy strikes into an immature profession which was already unconfident in its practices (Watson, 2012) but at the same time internet tracking tools and digitalized measuring instrument offers them an opportunity to professionalize the practice. Thanks to the ethnographic work realised in a communications department and the exploration of industry documents and events; this work shows three main postures adopted face to measurement: utilitarian, anxious, strategic and the different ways in which quantitative measurement has impacted internal conventions and restitution spaces.