This paper reports on the results of a survey of mathematics and science candidates for National Board for Professional Teaching Standards (NBPTS) certification. The goal of the survey was to investigate the efficacy of collaboration and group support in preparation for NBPTS. The results of the survey describe the nature of supported preparation, and the data of the survey are combined with final NBPTS scores to investigate relationships between preparation practices and outcomes. The results show that the subsamples in the areas of Early Adolescent Mathematics, Adolescent and Young Adult Mathematics, Early Adolescent Science, and Adolescent and Young Adult Science were similar in composition, and the respondents in each subsample produced very similar responses concerning their collaborative preparation experiences. Although this study shows that collaborative preparation resulted in higher scores and higher passing rates for most respondents, the nature of the effects across subsamples varied. The data clearly indicate that collaborative preparation is highly valued for motivational and instrumental support; however, less value is placed on practices that are reflective and content focused. The homogeneous nature of preparation revealed in the data and the likelihood that candidates are at different levels of readiness for the rigorous NBPTS assessment process are discussed, as is the need for more attention to candidates who prepare without the support of an organized group.