In 1999, the Thomas B. Fordham Foundation published a study by Dan Goldhaber (of the Urban Institute) and Dominic Brewer (of RAND) that found that students of teachers with emergency credentials do no worse than students whose teachers have standard teaching credentials. The study was later published in Educational Evaluation and Policy Analysis, a peer-reviewed journal of the American Educational Research Association. The Spring 2001 issue of Educational Evaluation and Policy Analysis contains a 20-page article by Linda Darling-Hammond, Barnett Barry, and Amy Thoreson that attacks the Goldhaber and Brewer study as well as some claims that have been made on the basis of that study, and reviews the literature on the impact of teacher certification on student achievement. In an 8-page reply appearing in the same issue, Goldhaber and Brewer respond to the charges. While the methodological debate may be too technical for lay readers, their brief review of the extremely weak research base often cited by proponents of teacher certification is very useful. Unfortunately these articles are not available online. Readers who would like to read them and don't have access to Educational Evaluation and Policy Analysis at a university library will have to order a back issue (Spring 2001) for $16 plus $3 postage (payable by Visa/Mastercard/check) from AERA. Write to AERA, Attention: Publications/Sales, 1230 17th St NW, Washington DC 20036; phone: 202-223-9485; fax: 202-775-1824.