The California Public Employees' Retirement System (CalPERS) is the largest public pension fund in the United States, established by legislation in 1931 following a 1930 constitutional amendment to provide retirement and health benefits to California public employees. Initially operating as the State Employees' Retirement System (SERS) from 1932, it expanded to include broader public employees and underwent name changes to Public Employees' Retirement System (PERS) in 1967 before adopting the CalPERS moniker in 1992 to distinguish it from similar systems in other states. Today it manages approximately $480 billion in global assets, serving more than 2 million current and retired members from over 3,000 public employers, including state agencies, schools, and local governments. CalPERS offers defined benefit pensions, with average annual benefits around $28,089 and monthly retiree payments of about $3,130, funded by employee contributions (typically 7-8% of salary), employer contributions (averaging 17.6%), and investment returns.

Governed by a 13-member Board of Administration comprising elected officials, appointees, and employee representatives, CalPERS focuses on sustainable, long-term investments to ensure retirement security, emphasizing risk-adjusted returns through diverse portfolios including equities, fixed income, real estate, and private equity. It has notable financial relationships, such as being a client of TPG Capital for alternative investments. The organization promotes an inclusive culture with diversity and inclusion initiatives, while actively engaging in stewardship activities like supporting the Paris Agreement on climate change and committing funds to clean energy. CalPERS also faces ongoing challenges, including funding pressures from market volatility and benefit expansions.

Headquartered in Sacramento, CalPERS plays a pivotal role in California's public sector workforce stability, administering health programs for over 1.5 million members and their families. Its investment decisions influence global markets, with a mandate for transparency and risk management. The fund's growth reflects California's public service ethos, but it has drawn scrutiny for investment risks and contribution requirements amid economic fluctuations.