It is recognized that masonry veneer walls, commonly used in commercial, industrial and residential buildings can be vulnerable to earthquakes and most of the reported cases of failures are due to poor materials, design and inadequate construction practices. This inadequate behaviour has promoted research on the seismic behaviour of brick veneer walls mostly attached to structural systems composed of light timber and steel frames but this work aims to contribute to the knowledge of seismic behaviour of masonry veneer whose backing support is composed by brick masonry infill walls enclosed in RC frames that is a construction system common in Portugal and South of European countries. In detail, this thesis aims at: (1) analyse at the local level the mechanical behaviour of connections of wall ties between the brick veneer walls and masonry infill walls; (2) assess the mechanical behaviour of brick veneer walls under out-of-plane loads for different configurations of ties; (3) carry out an overview of standards and provide design and construction guidelines under seismic action for brick masonry veneer walls. To accomplish this, an extensive experimental program was designed, being divided mainly in two phases: (1) mechanical and physical characterization of materials components, such mortar, bricks and brick masonry. An extensive experimental campaign on cyclic tension-compression and shear tests on different tie-masonry assemblages was performed. Different parameters were considered, namely the type of tie, width of the air cavity, mortar strength and embedment length of the ties; (2) cyclic out-of-plane tests on brick masonry veneer walls attached to brick masonry walls enclosed in a RC frame. In this experimental campaign it was also varied the type of ties, air cavity width, embedment length and the effect of previous in-plane loading. The experimental work is complemented with analytical tools to define hysteric laws to represent the cyclic tension-compression and shear behaviour of ties, which can be used in further numerical studies. It was concluded that the tension-compression behaviour of connections is influenced by the type of wall tie and air cavity width. The stiffness of tie and free length influences significantly the compression behaviour and the shape of tie and embedment length of the tie control the tensile behaviour. The out-of-plane behaviour of the brick veneer walls depend also on the type and number of ties, and on the air cavity width. Both parameters control the out-of-plane performance from the brick veneer walls to the backing wall.