The present article describes the development and initial validation of the Inventory of Microaggressions Against Black Individuals (IMABI) using a sample of 385 undergraduates who self-identified as Black or African American. The IMABI is a 14-item, unidimensional measure of racial microaggressions that captures both microinsults and microinvalidations. The present findings support the IMABI as a reliable and valid measure of microaggressions that was associated with general distress and perceived stress. Importantly, the association between the IMABI and psychological adjustment persisted even when social desirability and another measure of race-related stress were included in the analyses. Discussion focuses on the potential implications of the IMABI for understanding the daily experiences and psychological adjustment of Black individuals. (Contains 3 tables and 2 footnotes.)