Information graphics (such as bar charts and line graphs) play a vital role in many multimodal documents. Unfortunately, visually impaired individuals who use screen reader programs to navigate through such documents have limited access to the graphics. This paper presents the Interactive SIGHT (Summarizing Information GrapHics Textually) system that provides visually impaired individuals with the high-level knowledge that one would gain from viewing graphics in electronic documents. The current system, which is implemented as a browser extension, works on simple bar charts. Once launched by a keystroke combination, Interactive SIGHT first provides a brief initial summary that conveys the underlying message of the bar chart along with the chart's most significant features. The system is then able to generate history-aware follow-up responses that provide further information upon request from the user. User evaluations with sighted and visually impaired users showed that the initi...