The bimetallic welds (BMWs) play a critical and indispensable role in the primary heat transport piping system of nuclear reactors. The primary heat transport system in itself is the critical part of a nuclear reactor. Any failure of this system can lead to grave consequences, not only speaking of huge monetary losses resulting from non-utilization of the reactor setup, but also immensely valuable and irreparable loss of human life. The present paper is an effort towards identifying and understanding the problems affecting the BMWs and is as well an attempt to highlight the current issues in the structural integrity assessment of structures having these welds. The basic aim of this work is to provide a clear understanding of the current structural safety issues and their importance in underpinning the use of BMWs in modern nuclear reactors. © IMechE 2006.