"National Labor Relations Act (NLRA) was amended by the Taft-Hartley Act in 1947, allowing individual states to supersede the union security provisions of the NLRA by enacting laws that prohibit union security agreements. These state laws are known as right to work (RTW) laws."
The legislative history is described in a Congressional Research Service report, Right to Work Laws: Legislative Background and Empirical Research by Benjamin Collins.
National Conference of State Legislatures
Subject Compilations of State Laws (Hein Online) (Princeton only) (1960+)
See subjects: Collective Bargaining, Labor Relations, Right-to-Work Laws, Right to Work Laws
National Survey of State Laws
The electronic version [for 2005 5th edition (2005) and 6th edition (2008); Princeton only] is a collection of PDFs. In the search box under the thumbnail image of the publication cover, type Right to Work and click on the magnifying glass. Under the desired Right to Work entry, click on View Text.
Older print editions were published approximately every 5 years starting in 1993. Princeton has 1st edition (1993), 2nd edition (1997), 4th edition (2003), 6th edition (2008), and 7th edition (2015) in print. Location: Trustees Reading Room (DR) call number: KF386 .N38
4th edition (2003) also at: Stokes (SPIA). Call number.: KF386 .N38 2003
(search in catalog)