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Fatigue failures in engineering structures occur predominately at component connections, even in those structures that have been designed, fabricated, and inspected according to ACode.@ AConnections@ refers to those locations in a structure where elements are joined to reconcile changes in geometry and/or accommodate fabrication or service requirements. Given the preponderance of weld related fatigue failures, it is reasonable to expect that state-of-the-art design codes would incorporate rules or procedures for addressing the fatigue life of welded components. However, several design codes do not incorporate explicit fatigue life curves for welded components. Also, although the applied service stresses may be within Code design allowable for Afatigue rated@ components, welded and bolted connections can sufficiently elevate local stresses to initiate and propagate cracks. This Bulletin, examines the parameters that most affect the fatigue life of welded components, and the manner in which various codes address fatigue. Publication of this document - WRC Bulletin No. 422 was sponsored by the Pressure Vessel Research Council of the Welding Research Council, Inc.