On October 16, 2025, the four cities formalized their partnership through a Memorandum of Understanding establishing The BIG 4. This collaboration marks one of the first coordinated economic development partnerships of its kind in California, with cities aligning policies, incentives, and technical standards to attract and retain business investment.

The BIG 4 is an economic juggernaut. Collectively, The BIG 4 represents:

· 25% of Southern California’s industrial product

· Over 5 million square feet of retail, including the largest retail outlet mall in Los Angeles County

· 6 million square feet of suburban-adjacent office space

· The most robust utility availability in the region

· The most business-focused policies in the State

Understanding the growing competition from states like Texas, Arizona, Nevada, Tennessee, The BIG 4 came together to proactively strengthen their position and address the concern of businesses leaving the state. They understood that to compete with national markets, they needed to communicate the unique attributes of a coordinated, business-focused strategy designed to highlight the unique infrastructure, policy advantages and development readiness of the collective region. In other words, they need to be recognized as an economic hub.