The　toggle-brace-damper　system　(TBDS)　can　obviously　improve　the　energy　dissipation　efficiency　of　a　damper　by　amplifying　its　deformation.　The　small　deformation　solution　is　widely　used　to　characterize　the　amplification　capacity　of　the　TBDS.　However,　the　parameters　of　the　small　deformation　solution　are　not　mutually　independent.　Furthermore,　as　the　small　deformation　solution　is　a　constant,　it　cannot　comprehensively　characterize　the　mechanism　of　the　TBDS.　These　drawbacks　hinder　a　more　in-depth　study　of　the　TBDS　mechanism.　In　addition,　the　existing　TBDS　requires　a　large　building　space,　which　adversely　affects　the　layouts　of　doors　and　windows.　In　view　of　the　problems　above,　a　space-saving　local　toggle-brace-damper　system　(LTBDS),　as　an　extended　form　of　the　TBDS,　is　proposed.　The　displacement　amplification　factor　considering　the　large　deformation　effect　is　derived.　The　variation　law　of　this　amplification　factor　with　the　lateral　displacement　is　clarified.　The　local　toggle　energy　dissipation　device　(LTEDD),　which　consists　of　two　identical　and　symmetrically　arranged　LTBDSs,　is　recommended　to　overcome　the　LTBDS’　amplification　capacity　asymmetry.　The　effects　of　the　geometric　parameters　on　the　amplification　capacity　of　the　LTEDD　are　clarified.　A　geometric　optimization　method　to　improve　the　amplification　capacity　of　the　LTEDD　is　proposed　based　on　the　estimation　of　the　maximum　lateral　displacement　of　the　LTEDD　under　earthquakes.　To　estimate　the　maximum　lateral　displacement　of　the　LTEDD　and　calculate　the　additional　damping　ratio　contributed　by　the　LTEDD　damping　system,　the　storey　drift　utilization　ratio　is　proposed,　and　the　calculation　method　is　derived　and　verified.　Finally,　the　case　analysis　verifies　the　feasibility　of　the　LTEDD　and　the　effectiveness　of　the　optimization　method.　©　2022