The spectacular growth in income inequality in the United States has been driven in part by declines in the proportion of the labor force that is unionized. Because unions raise wages, and because unions are disproportionately concentrated in the lower-wage manual sector, the decline of unions has created a more polarized income distribution. The size and strength of unions could be altered through simple changes in the laws governing how unions are organized and how collective bargaining should unfold. Should such changes be considered? For more information on current labor law, consult the site for the National Labor Relations Board.