Following the successful crowdsourcing project involving Swissair retirees (2009–2013), ETH Library’s Image Archive set up a comments function on its image database at the end of 2015. On 18 January 2016, the Neue Zürcher Zeitung (NZZ) reported on it and triggered a huge response in both the media and the general public, who are now helping to identify images. This article focuses on our experiences with public crowdsourcing in relation to the amendments on the image database, the volunteers’ approach, the internal editing workflow and the communication with the volunteers. Community care is a key factor for successful crowdsourcing initiatives. The most important instruments tested in the image archive are presented and discussed. In order to get to know the unknown crowd better, an online survey on the motivation, work techniques and sociodemographic background among the crowd was conducted in early 2017. The results of this survey will be showcased in the presentation.