We show that: (1) if R is a Noetherian domain, then R[{X-lambda}(lambdais an element ofLambda)](1) is a strong Mori domain; (2) if R is a strong Mori domain, then R[{X-lambda}(lambdais an element ofLambda)](1) is a Mori domain; but (3) there exists a strong Mori domain R such that R[X] is not a strong Mori domain. (C) 2003 Elsevier Inc. All rights reserved.