It took years for the Treaty of Rome's dream of a single labor market to come to fruition, but now — cue joke about Polish plumbers — the right to live, work, and indeed retire, in another Union country is established, and such freedoms will gradually be extended to citizens from the 12 countries that joined since 2004. This means working to the same rules, too; though national legislatures had taken the lead, the Treaty itself enshrined the principle of equal pay for equal work for men and women, while the 2000 Charter of Fundamental Rights proclaims workers' entitlements on issues from labor mobility and collective bargaining to equal opportunities.