Thousands of RC buildings were severely damaged or collapsed in Turkey during the past major earthquakes due to various deficiencies. This has initiated extensive experimental studies on strengthening methods. In this study, two 1/3-scale, two-story, three-bay undamaged frames were tested to compare two types of strengthening techniques experimentally. Both undamaged frames were designed such that they had the common deficiencies of existing buildings in Turkey. One of the frames was strengthened with RC infill while the other frame was strengthened with CFRP strengthened hollow clay blocks. The test specimens were subjected to reversed cyclic quasi-static loading. To measure the internal forces at the base of exterior columns special transducers were used. Strength, stiffness, and story drifts of the test specimens were evaluated. It is observed that both strengthened frames behaved similarly under reversed cyclic lateral loading. (c) 2006 Elsevier Ltd. All rights reserved.