Modern construction technologies attempt to fortify buildings by preventing easy entry by intruders, using fences and gates, anti-burglar to windows and doors, and discouraging using illumination at night. This book examined the predictability of the probable cost of providing security in building projects; by determining the relationships between the total costs of built-in security components and some physical characteristics of buildings. The study that tested the influence of numbers of external openings returned a statistically significant result. Similarly, the study shows that the total costs of built-in security differed significantly amongst the various uses of the building. Also, revealed a variations in the costs of security across the selected locations. However, architectural designs for buildings should always include built-in security components which could forestall any future breach of security in different types of buildings, such as commercial, residential building and the likes.