An infrastructure project is a construction project that involves laying, building, or maintaining physical networks that are essential to the operation of a society, economy, or industry. Its work requires specialized knowledge of engineering, building materials, and a variety of machinery and equipment. It often takes place in densely populated areas with frequent, high volume traffic. It has to be designed and built for durability. It is typically more complex and time-consuming than other types of construction projects. Its projects are usually large in scale and have to meet a strict set of standards.

The defining characteristics of infrastructure are that it provides services, has significant capital costs, and affects the quality of life of citizens. It is critical for economic growth, because it can stimulate business activity and job creation. It helps with social development because it improves access to water, electricity, and transportation. It also helps with environmental and sustainability issues, such as by reducing greenhouse gas emissions, providing renewable energy, and waste management.

Infrastructure projects can be built by private companies or the public sector. The latter has the advantage of being less dependent on the vagaries of the market, and may be better able to plan long-term. However, it is often subject to political influence from elected officials who are trying to buy votes by promising new projects. Public-private partnerships, or P3s, are a way for governments to overcome these challenges and bring in more funding.