In this thtesis, the boundary Element Method (BEM) for the analysis of crack growth in concrete structures is presented. The analysis is based onthe Dual Boundary Element Method (DBEM) to represent the caracks in concrete and the Fictitious Crack Model (FCM) to represent the fracture process zone in concrete. A tensile fracture zone inconcrete is assumed to develop when the stress at any point exceeds the maximum tensile strength of the materials. The fracture zone undergoes an additional deformation but is still able to transfer the stresses as long as the deformation is small. The stress transferring capability is assumed according to a stress-deformation curve. In the numerical analysis, the process zone is modified by aplying closing forces on both surfaces of a fictitious crack. The FCM in conjunction with the DBEM allows the simulation of carack growth in concrete in straight forward manner. The DBEM is based on the displacement boundary integral equation which is applied on one crack problems can be performed effectively in a single region formulation. The advantage of using this method is that for every carack extension increment,no remeshing is required. The crack increment direction is computedfrom the previous step. The requirement of crack is tahat the stress at the crack tip must exceed the maximum tensile stress of the material. A procedure to calculate tht stress at aht carack tip is presented together with the algorithm for the crack growth. The algorithm presented is controlled by the crack extension increment which acts as a monotonic increasing function. The dual Boundary Element formulation is extended to include the reinforacement in the concrete. The theoretical modelling of the reinforcement in terms of the unknown attachment force distribution is presented. The solution for the attachment forces is obtained from the condition that the deformation of the concrete and the reinforcement is compatibleunder the action of external loading. In the present work, the bond between concrete and reinforcement is assumed to be perfect. The application of DBEM for modelling the cracking in the pullout test is presented sing contact analysis. The contact is assumed between the anchor head of the bolt and the concrete. A series of benchmark examples are presented in this thesis for the application of crack growth in concrete structures and shown to be in good agreement with Finite Element and experimentalresults.