Expansionary fiscal policy is a government strategy used to stimulate economic activity when an economy is experiencing slow growth, high unemployment, or a recession. It works primarily by increasing government spending, reducing taxes, or using a combination of both. The objective is to increase aggregate demand, encourage business activity, create jobs, and support overall economic growth.

When the government increases spending on areas such as infrastructure, healthcare, education, or public services, more money enters the economy. This can increase demand for goods and services, encouraging businesses to produce more and potentially hire additional workers. Similarly, tax cuts can increase the disposable income of households and improve their ability to spend. Lower taxes on businesses may also encourage investment and expansion.

Expansionary fiscal policy can be particularly useful during economic downturns. By supporting demand, it can help reduce the effects of a recession and close a recessionary output gap. However, it also has potential disadvantages. If government spending increases too rapidly or tax reductions are too large, demand may rise faster than the economy's productive capacity, creating inflationary pressure.

Another consideration is government borrowing. Expansionary policies may increase budget deficits if additional spending is not matched by higher government revenue. Persistent deficits can contribute to rising public debt and may create financial challenges over the long term.

Overall, expansionary fiscal policy is an important economic tool for supporting growth and employment during weak economic conditions. Its effectiveness depends on factors such as the size and timing of government measures, economic conditions, consumer behavior, and the economy's available productive capacity.