This study examines the determinants and consequences of broker in-house ESG research. Using manually collected brokerage ESG research data, we find that the provision of in-house ESG research is positively related to both demand-side factors (client demand, internal demand, and local ESG awareness) and supply-side factors (broker size and coverage of sustainable industries). Regarding the consequences of such research, we find that in-house ESG research is associated with improved earnings forecast accuracy in industries where ESG is more salient. Further, the market reaction to earnings forecast revisions is stronger when equity analysts have access to in-house ESG research. Finally, we observe a consistent pattern suggesting that ESG analysts support equity analysts beyond forecast accuracy, as equity analysts with access to in-house ESG research issue more accurate target prices, more informative recommendation upgrades for ESG-heavy industries, and discuss ESG issues more extensively in their analyst reports. Data Availability Statement: The data used in this study are obtained from publicly available sources identified in the paper, as well as job posting data licensed from Lightcast. Sample construction procedures are described in the paper. Researchers interested in the job posting data should contact Lightcast directly, as access is subject to licensing restrictions.