This paper describes a system for assistive writing, the Speech Supplemented Word Prediction Program (SSWPP). This system uses the first letter of a word typed by the user as well as the user’s (possibly low-intelligibility) speech to predict the intended word. The ASR system, which is the focus of this paper, is a speaker-dependent isolated-word recognition system. Word-level results from a non-dysarthric speaker indicate that almost all errors could be corrected by the SSWPP language model. Results from five speakers with moderate to severe dysarthria (average intelligibility 61.7%) averaged 62% for word recognition and 65% for out-of-vocabulary identification.