General considerations regarding the conservation of historic buildings in seismic zones -- Criteria and objectives -- Retrofitting approaches -- Overview of Byzantine churches -- Architecture -- Frescoes -- Types of Byzantine churches -- Structural characteristics -- Surface characteristics -- Survey of existing Byzantine churches in Macedonia -- Present state of selected church buildings, causes and level of damage -- Authenticity -- Churches selected for detailed investigation -- The church of St. Nikita, Banjani -- Proposed strengthening method and preliminary analysis of the retrofitted St. Nikita Church -- Possible methods for repair and strengthening of historic structures -- Design of the St. Nikita Church model -- Model construction -- Wall element tests -- Shaking-table tests of the St. Nikita Church model -- Tests of the original church model -- Repair and strengthening of the damaged model -- Tests of the repaired and strengthened church model -- Analytical modeling of the dynamic behavior of masonry structures exposed to earthquake motions -- Dynamic analysis of the nonlinear response of an idealized single-degree-of-freedom system -- Dynamic equations of motions -- Models of hysteretic behavior -- Analytical studies and correlation of the behavior of the two models -- Original model -- Strengthened model -- The bearing and deformability capacities of the model structures at the design and maximum levels of expected ground motion -- Capacity analysis of masonry buildings -- Mathematical model of the Byzantine church structure -- Analysis of structural walls -- Calculation procedure -- Results from the MASAN program for the original St. Nikita model -- Results for the strengthened church model -- Bearing capacity of the church model structure -- Capacity analysis of existing Byzantine church structures -- Analysis of St. Nikita, Banjani -- Analysis of St. Bogorodica Zahumska, Trpejca -- Analysis of St. Nikola, Psaca -- Analysis of St. Bogorodica, Matejce -- Analysis of St. Gjorgji, Kurbinovo -- Implementation of methods for repair and strengthening of Byzantine church structures -- Possible methods and techniques for repair and strengthening of historic Byzantine churches -- Repair and strengthening of historic monuments in accord with the experimentally verified methodology -- Strengthening of the structures of three representative churches -- Summary, conclusions, and recommendations -- List of churches surveyed -- Single-degree-of-freedom analysis flowchart -- Experimental and analytical displacement and acceleration time history -- Results of dynamic response analysis of the existing St. Nikita Church using the IZIIS hysteretic model.