In this study we report the results of survey research that collected responses of an identical sample (31 beginning mathematics and science teachers, elementary and middle school level) that graduated from a reform-based mathematics and science teacher preparation program, the Maryland Collaborative for Teacher Preparation (MCTP). Our aim was to compare responses of the same beginning teachers over the two administrations of the survey. We administered the identical survey instrument in two separate batches spreading over nearly a four-year period (1st batch fall 1999 through fall 2001; 2nd batch summer 2002). The first administration (pre-test) was conducted soon after the beginning teachers graduated from the teacher preparation program and had not started full teaching. The second administration (post-test) was conducted after the new teachers had taught full time for a minimum of a full year, with the majority having taught for two years. The instrument was crafted to measure the constructs of interest, MCTP Teacher's Beliefs and Actions of Mathematics and Science. Results for teachers who taught for at least two years indicated that in all areas the MCTP teachers "maintained" their reform-based beliefs and actions after their induction years. These findings provide evidence for the sustainability of positive impact in the workplace resulting from a reform-based undergraduate teacher preparation program. (Contains 2 tables and 1 figure.)