We present a multi-site field study to evaluate LemonAid, a crowdsourced contextual help approach that allows users to retrieve relevant questions and answers by making selections within the interface. We deployed LemonAid on 4 different web sites used by thousands of users and collected data over several weeks, gathering over 1,200 usage logs, 168 exit surveys, and 36 one-on-one interviews. Our results indicate that over 70% of users found LemonAid to be helpful, intuitive, and desirable for reuse. Software teams found LemonAid easy to integrate with their sites and found the analytics data aggregated by LemonAid a novel way of learning about users’ popular questions. Our work provides the first holistic picture of the adoption and use of a crowdsourced contextual help system and offers several insights into the social and organizational dimensions of implementing such help systems for real-world applications.