Altmetrics are tools for measuring the impact of research beyond scientific communities. In general, they measure online mentions of scholarly outputs, such as on online social networks, blogs, and news sites. Some stakeholders in higher education have championed altmetrics as a new way to understand research impact and as an alternative or supplement to bibliometrics. Contrastingly, others have criticized altmetrics for being ill conceived and limited in their use. This chapter explores the values and limits of altmetrics, including their role in evaluating, promoting, and disseminating research.