Allowing small business establishments in residential zones.

SB 5421 allows certain small businesses to operate in residential zones across Washington state, directly affecting cities and towns (which must permit these businesses) and qualifying small business owners. The bill defines "neighborhood businesses" as specific types: small food venues (500-2,000 sq ft), local retail stores (up to 10,000 sq ft), licensed childcare centers (serving ≤45 children), and low-impact professional services (≤3 full-time staff). Cities must permit these businesses in residential areas while imposing reasonable rules on noise, signage, hours (minimum 12 hours/day), deliveries, and alcohol sales - without restricting existing licensed operations. The law aims to support local economies and community spaces without altering neighborhood character, requiring cities to adopt compatible regulations.