The　existing　design　rules　give　quite　general　guidelines　to　the　fatigue　assessment　of　different　types　of　welded　joints.　The　goal　of　this　investigation　was　to　give　designers　some　tools,　which　would　allow　more　precise　assessment　of　the　effect　of　dimensional　variations　on　the　fatigue　strength.　Therefore　the　fatigue　behaviour　of　12　common　types　of　welded　joints　has　been　studied　parametrically.　Two-dimensional　(2D)　finite　element　models　of　the　joint　were　made　and　evaluated　using　plane　strain　linear　elastic　fracture　mechanics　(LEFM)　calculations.　The　as-welded　condition　was　assumed　with　the　result　that　no　crack　initiation　period　was　considered　and　stress　ranges　were　fully　effective.　A　maximum　tangential　stress　criterion　with　the　Paris＇　crack　growth　law　was　used　to　predict　the　growth　rate　and　direction　of　root　and　toe　cracks　under　mixed　mode　KI-KII　conditions.　The　effects　of　weld　size　and　joint　dimension　ratios　on　the　fatigue　strength　were　systematically　studied.　In　addition　to　tensile　loading,　bending　and　combined　tension/　bending　moment　loading　in　both　directions　are　examined　for　positive　and　negative　mean　stress.　©　2004　Elsevier　Ltd.　All　rights　reserved.