The focus of organizations' internal communication and collaboration infra-structures has recently been extended from conventional intranets to enterprise social software platforms (ESSPs). However, as ESSPs rely on content creation and interaction through users, many platforms struggle. Previous research sug-gests that organizational climate plays an important role during IS adoption. Accordingly, our study quantitatively explores the influence of organizational climate on both contributive ESSP usage (knowledge sharing) and consumptive ESSP usage (knowledge consumption). Our results indicate that organizational climate - measured by the dimensions of trust, collaboration norms, and com-munity identification - influences employees' ESSP usage behaviors to a certain extent. In addition, collaboration norms appear to have a stronger impact on consumptive ESSP usage than on contributive ESSP usage. Lastly, trust was found to primarily support consumptive ESSP usage, not contributive usage.