The Conrad Hilton, a 5-star prominent hotel in downtown Istanbul, was built in 1980. The “S” shaped building structure was originally designed as 3 independent blocks separated by expansion joints. Previously, the building was retrofitted by means of steel ropes at floor levels to control the huge relative displacements at the expansion joints. Miyamoto Turkey performed detailed surveying, structural assessment by 3-D non-linear time history analyses, retrofit design for minor modifications on structural system due to enlargement of rooms and upgrading the shear resistance of various structural members, cost planning and budgeting, construction supervision and preparing the final drawings and documents for resulting structural system.