Temper embrittlement of a 2.25Cr1Mo steel is evaluated by use of small punch testing with disc specimens. Clearly, a ductile-to-brittle transition temperature of the steel may be determined by this test, but the value obtained is much lower than that determined by the standard Charpy test. The steel exhibits some temper embrittlement when tempered at 400 degrees C for 86 days. (C) 2000 Elsevier Science S.A. All rights reserved.