Infrastructure (also known as "capital goods", or "fixed capital") is a platform for governance, commerce, and economic growth and is "a lifeline for modern societies". It is the hallmark of economic development.

It has been characterized as the mechanism that delivers the "..fundamental needs of society: food, water, energy, shelter, governance ... without infrastructure, societies disintegrate and people die." Adam Smith argued that fixed asset spending was the "third rationale for the state, behind the provision of defense and justice." Societies enjoy the use of "...highway, waterway, air, and rail systems that have allowed the unparalleled mobility of people and goods. Water-borne diseases are virtually nonexistent because of water and wastewater treatment, distribution, and collection systems. In addition, telecommunications and power systems have enabled our economic growth."

This development happened over a period of several centuries. It represents a number of successes and failures in the past that were termed public works and even before that internal improvements. In the 21st century, this type of development is termed infrastructure. Infrastructure can be described as tangible capital assets (income-earning assets), whether owned by private companies or the government.

Infrastructure may be owned and managed by governments or by private companies, such as sole public utility or railway companies. Generally, most roads, major ports and airports, water distribution systems and sewage networks are publicly owned, whereas most energy and telecommunications networks are privately owned. Publicly owned infrastructure may be paid for from taxes, tolls, or metered user fees, whereas private infrastructure is generally paid for by metered user fees. Major investment projects are generally financed by the issuance of infrastructure bonds, specialized long-term bonds, which (often) offer interest and tax benefits.

Hence, government owned and operated infrastructure may be developed and operated in the private sector or in public-private partnerships, in addition to in the public sector. In the United States, public spending on infrastructure has varied between 2.3% and 3.6% of GDP since 1950. Many financial institutions invest in infrastructure.

Infrastructure debt is a complex investment category reserved for highly sophisticated institutional investors who can gauge jurisdiction-specific risk parameters, assess a project’s long-term viability, understand transaction risks, conduct due diligence, negotiate (multi)creditors’ agreements, make timely decisions on consents and waivers, and analyze loan performance over time.

Research conducted by the World Pensions Council (WPC) suggests that most UK and European pensions wishing to gain a degree of exposure to infrastructure debt have done so indirectly, through investments made in infrastructure funds managed by specialised Canadian, US and Australian funds.

On November 29, 2011, the British government unveiled an unprecedented plan to encourage large-scale pension investments in new roads, hospitals, airports, etc. across the UK. The plan is aimed at enticing 20 billion pounds ($30.97 billion) of investment in domestic infrastructure projects.