North Park Main Street is a private nonprofit organization charged with the revitalization of the North Park Business Improvement District (BID), North. -- North Park Main Street is both a business improvement district established by the City of San Diego, and a Main Street program affiliated with the National Trust for Historic Preservation. As a volunteer-based, 501(c)(6) non-profit organization, North Park Main Street (NPMS) advocates for North Park’s business community, administers the North Park Business Improvement District (BID), and champions development that preserves the community’s historic integrity, supports its Arts, Culture & Entertainment District, and promotes an urban, pedestrian-friendly shopping / dining environment.