Knowledge management systems (KMSs) facilitate the efficient and effective sharing of a firm's intellectual resources. However, sifting through the myriad of content available through KMSs can be challenging, and knowledge workers may be overwhelmed when trying to find the content most relevant for completing a new task. To address this problem, KMS designers often include content rating schemes (i.e., users of the KMS submit ratings to indicate the quality of specific content used) and credibility indicators (indicators describing the validity of the content and/or the ratings) to improve users' search and evaluation of KMS content. This study examines how content ratings and credibility indicators affect KMS users' search and evaluation processes and decision performance (how well and how quickly users selected alternatives offered by the KMS). Four interrelated laboratory experiments provide evidence that ratings have a strong influence on KMS search and evaluation processes, which in turn affects decision performance. Finally, this study demonstrates that certain credibility indicators can moderate the relationship between rating validity and KMS content search and evaluation processes.