EPA has undertaken a comprehensive, preliminary reassessment of the time limited registrations for all Bacillus thuringiensis (Bt) corn and cotton plant-pesticides that will be reviewed for registration renewal in the fall of 2001.  This reassessment has been designed to assure that the decisions on the renewal of the corn and cotton registrations are based on the most current health and ecological data (including recently reviewed non-target impact data) and incorporates recommendations made by the March 1995, February 1998, and December 1999 FIFRA Scientific Advisory Panel (SAP) and the findings of the 1999 National Academy of Sciences (NAS) report on Genetically Modified Pest- Protected Plants.  The June 2000 SAP report has not yet been received, but will be considered when this assessment is finalized.  Also included in this assessment is the data that supports the registration of the NatureMark Bt potato as well as data developed in support of a number of plant-pesticides that are no longer produced or will not be seeking registration renewal. In the interest of assuring a truly comprehensive review, it is EPA's intention to present and assess the full range of data and information available.The complete reassessment document is fashioned after the Agency's traditional Reregistration Eligibility Document (RED). This format was selected to present the data and findings in a format that is familiar to the registrants, the users and the general public.  The Bt Plant-Pesticides Biopesticides Registration Action Document (BRAD) Preliminary Risk and Benefits Sections document has five major sections:1. Product Characterization2. Human Health Assessment3. Ecological Assessment4. Insect Resistance Management5. Benefits.The Executive Summary includes one additional section, Other Considerations.