Recently there is widespread interest in women's underrepresentation in science, technology, engineering, and mathematics (STEM); however, progress toward gender equality in these fields is slow. More alarmingly, these gender disparities worsen when examining women's representation within STEM departments in academia. While the number of women receiving postgraduate degrees has increased in recent years, the number of women in STEM faculty positions remains largely unchanged. One explanation for this lack of progress toward gender parity is negative and pervasive gender stereotypes, which may facilitate hiring discrimination and reduce opportunities for women's career advancement. Women in STEM also have lower social capital (e.g., support networks), limiting women's opportunities to earn tenure and learn about grant funding mechanisms. Women faculty in STEM may also perceive their academic climate as unwelcoming and threatening, and report hostility and uncomfortable tensions in their work environments, such as sexual harassment and discrimination. Merely the presence of gender-biased cues in physical spaces targeted toward men (e.g., "geeky" décor) can foster a sense of not belonging in STEM. We describe the following three factors that likely contribute to gender inequalities and women's departure from academic STEM fields: (a) numeric underrepresentation and stereotypes, (b) lack of supportive social networks, and (c) chilly academic climates. We discuss potential solutions for these problems, focusing on National Science Foundation-funded ADVANCE organizational change interventions that target (a) recruiting diverse applicants (e.g., training search committees), (b) mentoring, networking, and professional development (e.g., promoting women faculty networks); and (c) improving academic climate (e.g., educating male faculty on gender bias).