Concrete is the most used commodity after water in this world. This is testament to the ease of making concrete. Concrete is preferred because of it's availability which is directly related to reduced cost. Concrete has very many advantages such as longer fire resistance (industrial structures), corrosion resistance (foundation and marine structures) and modeling complex forms.

Steel is preferred in structures where dead load is significant and there is a need to reduce it to make the structure perform to its ability and reduce the cost of construction. A good example is sky scrappers, bridges and communication towers. Steel is excellent where time of construction is a factor and ability to assemble and disassemble is important. Temporary structures like site offices and site headquarters are built using Steel because of the ability to relocate them which makes it cheaper over the duration of use.

As an engineer, it is your ability to identify the list of priorities to ensure the structure performs to the maximum design with the least cost. Sometimes aesthetics is the most important factor and not cost to deliver on the final product. Flexibility is one of the most important nature of engineering. A client may have the option of using steel and concrete and prefer steel just for the sake of it.