ABSTRACT: Invasive, exotic insects and diseases have had, and will continue to have, a devastating ecological and economic impact on North American forests. The rate of spread, or rate of range expansion, is one of the main determinants of an invasive organismís impact as well as management response options. Unfortunately, there are numerous examples available help us understand how exotic organisms have spread through our forests. This study uses a consistent, rigorous analytical framework to examine a comprehensive geospatial database of the spread of seven exotic insects and six diseases in North America. The analysis of nearly 3,000 records of infestation demonstrates that insects and diseases have expanded their ranges at similar rates. On average, exotic insects and diseases have spread about 12 miles per year; though some recently introduced organisms have spread faster than 30 miles a year.