The National Center for Research on Evaluation, Standards, and Student Testing (CRESST) has been laying the groundwork to explore fundamental questions of the implementation of alternative assessment. The CRESST has been working collaboratively with school practitioners to help them implement performance assessment strategies so that the CRESST could better understand the implementation process and investigate barriers and facilitators to assessment innovation. CRESST methods are described, findings are discussed, and some examples are presented of the performance assessment materials developed by study participants. At a variety of sites, alternative assessment was studied in social studies, the humanities, and mathematics. A generic survey (15 teachers and administrators from 3 schools) and a specialized survey (11 teachers in a portfolio project and 7 teachers in a journal project) provided data about the implementation of performance assessment. Conclusions about barriers and facilitators of implementation are summarized. Overall, teachers and administrators saw positive effects from alternative assessment. Four appendixes contain two teacher surveys, a summary of impact and implementation findings, and four examples of alternative assessments. Four figures illustrate survey findings. (SLD)