Soil bearing capacity is one of the fundamental factors in the design of building and structure foundations, as the safety and stability of a structure depend on the soil’s ability to resist the loads transferred to it without shear failure or excessive settlement. Evaluating the geotechnical properties of soil is therefore a necessary step to ensure the efficiency of structural design and reduce future risks. Soil Bearing Capacity and the Factors Affecting It Soil bearing capacity is defined as the soil’s ability to resist the stresses resulting from foundation loads while maintaining the stability of the structure. This capacity is influenced by several factors, chiefly the type of soil, its density and shear strength, the depth of foundation and the foundation dimensions, the groundwater level, as well as the nature, magnitude, and distribution of the loads. The properties of sandy soils differ from those of clayey soils in terms of strength and compressibility, which calls for careful geotechnical investigations to determine the properties of the soil layers and choose the appropriate engineering solution. Methods of Evaluating Bearing Capacity Soil bearing capacity is determined based on a set of field and laboratory tests, including the Standard Penetration Test (SPT), the Cone Penetration Test (CPT), the plate load test, in addition to laboratory shear strength and compressibility tests. The results of these tests are used to estimate soil strength and evaluate its behavior under loading. Engineering relationships and theories, including Terzaghi’s theory, are also employed in calculating bearing capacity, taking into account the soil type, foundation shape, foundation depth, and groundwater conditions. The Effect of Bearing Capacity on Foundation Design Soil bearing capacity directly affects the choice of foundation type, its dimensions, and its depth. When the surface layers have suitable strength, shallow foundations can be adopted, such as isolated and combined footings, strip foundations, or mat foundations. Where weak layers exist or the expected settlement exceeds acceptable limits, it may be necessary to consider the use of deep foundations, such as piles. Safe design is not limited to ensuring that the bearing capacity is not exceeded; it also includes calculating total and differential settlement, since uneven settlement can lead to cracks in walls and structural members and may affect the safety and performance of the structure. Conclusions and Recommendations It is clear that evaluating soil bearing capacity is an important basis for designing foundations safely and economically. The success of the design depends on the accuracy of geotechnical investigations, the analysis of test results, and consideration of loads, soil properties, and groundwater level, along with verification of resistance to failure and expected settlement. The article recommends carrying out soil tests before implementing construction projects, adopting their results in selecting the foundation type and determining its dimensions, and complying with the approved engineering codes, thereby helping to reduce structural risks and achieve the sustainability of buildings and structures. References Terzaghi, K., Peck, R. B., & Mesri, G. (1996). Soil Mechanics in Engineering Practice. 3rd ed., John Wiley & Sons. Das, B. M., & Sivakugan, N. (2019). Principles of Foundation Engineering. 9th ed., Cengage Learning. Bowles, J. E. (1996). Foundation Analysis and Design. 5th ed., McGraw-Hill.