Also known as a dual gate system or two-gate system. A procedure recognized under the National Labor Relations Act (NLRA) for creating separate entrances to a premises or worksite for primary employers and neutral employers, so that any primary union picketing against the primary employer does not interfere with neutral employers' business at a workplace location, facility or site shared with multiple employers, often called a common situs.

The procedure is based on the National Labor Relations Board's (NLRB) holding in Sailors’ Union of the Pacific (Moore Dry Dock) (see 92 N.L.R.B. 547 (1950)). Under cases following Moore Dry Dock, a union's picketing at entrances designated for neutral employers at a common situs may be evidence that the union has an unlawful secondary intent of harming those neutral employers so that they stop doing business with the primary employer, which is an unfair labor practice (ULP). For more information, see Standard Document, Reserved Gate Guidelines.

For more information about union picketing and strikes, see Practice Notes, Strikes Under the National Labor Relations Act and Picketing Under the National Labor Relations Act.

For information about the NLRB's processing of ULP charges, see National Labor Relations Board Unfair Labor Practice Case Flowchart.